docs(sitestream): document aggregated live alarm stream + resolve deferred #10 (plan #10 T8)

Alarm Summary is now live-cache-driven via a transient per-site central
live alarm cache (ISiteAlarmLiveCache) fed by a site-wide, alarm-only
SubscribeSite gRPC stream (seed-then-stream), with the 15s poll retained
as fallback + NotReporting authority. No persisted central alarm store
([PERM]). Updated Component-CentralUI, Component-Communication (new §6.1
+ SubscribeSite RPC), M7 design (T13 delivered note), native-alarms
[PERM] note, stillpending follow-up note, CLAUDE.md, and moved register
row #10 to Resolved (left #22 in place for the sibling branch).

Claude-Session: https://claude.ai/code/session_01MtdgwpEeCUn6cUA5f1LMPj

CLAUDE.md

@@ -124,7 +124,7 @@ Other peers in the `scadaproj` family (see `scadaproj/CLAUDE.md` for details): `
 - Inter-cluster communication uses two transports: ClusterClient for command/control (deployments, lifecycle, subscribe/unsubscribe handshake, snapshots) and gRPC server-streaming for real-time data (attribute values, alarm states). Both CentralCommunicationActor and SiteCommunicationActor registered with receptionist. Central creates one ClusterClient per site using NodeA/NodeB as contact points. Sites configure multiple central contact points for failover. Addresses cached in CentralCommunicationActor, refreshed periodically (60s) and on admin changes. Heartbeats serve health monitoring only.
 - gRPC streaming channel: SiteStreamGrpcServer on each site node (Kestrel HTTP/2, port 8083); central creates per-site SiteStreamGrpcClient via SiteStreamGrpcClientFactory. Site entity has GrpcNodeAAddress/GrpcNodeBAddress fields. Proto: sitestream.proto with SiteStreamService, SiteStreamEvent (oneof: AttributeValueUpdate, AlarmStateUpdate). DebugStreamEvent message removed (no longer flows through ClusterClient).
 - Native alarms: a read-only mirror of native alarms from OPC UA Alarms & Conditions servers and the MxAccess Gateway, unified onto an A&C-style condition model (`AlarmConditionState`: orthogonal Active/Acked/Confirmed/Shelved/Suppressed + 0–1000 severity) plus an `AlarmKind` discriminator (Computed/NativeOpcUa/NativeMxAccess). New DCL capability seam `IAlarmSubscribableConnection` (implemented by the OPC UA and MxGateway adapters); the `DataConnectionActor` opens ONE alarm feed per connection and routes transitions to instances by source-object reference. A `NativeAlarmActor` (peer to the computed `AlarmActor` under `InstanceActor`) mirrors one source binding: snapshot atomic-swap on (re)subscribe, retention (drops once inactive+acked), per-source cap, and site SQLite persistence (`native_alarm_state`, survives failover, cleared on redeploy/undeploy — mirrors static overrides). State streams to central over the additively-enriched gRPC `AlarmStateUpdate` (the existing computed `AlarmStateChanged` was enriched additively) and seeds via the DebugView snapshot. Authoring: `TemplateNativeAlarmSource` / `InstanceNativeAlarmSourceOverride` entities flatten to `ResolvedNativeAlarmSource` (inherit/compose/override); management commands + ManagementActor handlers + CLI (`template/instance native-alarm-source`) + Central UI (template editor tab + instance override panel) + enriched DebugView alarm table. Read-only — no ack-back; no central tables.
-- OPC UA / MxGateway UX (M7): operator **Alarm Summary** page (`/monitoring/alarms`, RequireDeployment, read-only) fans out the existing per-instance `DebugViewSnapshot` Ask (SemaphoreSlim-capped, partial-results tolerant) and aggregates client-side — no central alarm store, no aggregated live stream yet (follow-up); shared `AlarmStateBadges` component. OPC UA node browser gains `BrowseNext` continuation paging ("Load more"), a bounded recursive address-space **search** (`IAddressSpaceSearchable` seam; depth + result caps; substring on DisplayName/path), and **type-info** (DataType/ValueRank/Writable on `BrowseNode` for Variables). Attribute-override **CSV bulk import** (`OverrideCsvParser`, all-or-nothing) via InstanceConfigure `InputFile` + CLI `instance import-overrides --file` (native-alarm-source-override CSV deferred). **Verify-endpoint** probe (temporary `RealOpcUaClient`, short timeout, captures an untrusted server cert but NEVER trusts it) + **site-local cert trust**: per-node `CertStoreActor` (runs on every site node, not a singleton) writing the `.der` into the node's OPC UA trusted-peer PKI store; DeploymentManager broadcasts `TrustServerCertCommand`/`RemoveServerCertCommand` to BOTH site nodes so PKI stores stay consistent across failover; Admin-gated cert-management UI (`/design/connections/{id}/certificates`). No central persistence of cert trust (follow-up).
+- OPC UA / MxGateway UX (M7): operator **Alarm Summary** page (`/monitoring/alarms`, RequireDeployment, read-only) fans out the existing per-instance `DebugViewSnapshot` Ask (SemaphoreSlim-capped, partial-results tolerant) and aggregates client-side — no central alarm store; shared `AlarmStateBadges` component. **Aggregated live stream shipped 2026-07-10** (`docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`): a transient in-memory per-site central live cache (`ISiteAlarmLiveCache`) fed by a site-wide, alarm-only `SubscribeSite` gRPC stream (seed-then-stream), pushing near-real-time deltas to the page over the Blazor circuit with the 15s poll kept as fallback + NotReporting authority — still no persisted central alarm store. OPC UA node browser gains `BrowseNext` continuation paging ("Load more"), a bounded recursive address-space **search** (`IAddressSpaceSearchable` seam; depth + result caps; substring on DisplayName/path), and **type-info** (DataType/ValueRank/Writable on `BrowseNode` for Variables). Attribute-override **CSV bulk import** (`OverrideCsvParser`, all-or-nothing) via InstanceConfigure `InputFile` + CLI `instance import-overrides --file` (native-alarm-source-override CSV deferred). **Verify-endpoint** probe (temporary `RealOpcUaClient`, short timeout, captures an untrusted server cert but NEVER trusts it) + **site-local cert trust**: per-node `CertStoreActor` (runs on every site node, not a singleton) writing the `.der` into the node's OPC UA trusted-peer PKI store; DeploymentManager broadcasts `TrustServerCertCommand`/`RemoveServerCertCommand` to BOTH site nodes so PKI stores stay consistent across failover; Admin-gated cert-management UI (`/design/connections/{id}/certificates`). No central persistence of cert trust (follow-up).
 
 ### External Integrations
 - External System Gateway: HTTP/REST only, JSON serialization, API key + Basic Auth.

docs/plans/2026-05-29-native-alarms-design.md

@@ -21,7 +21,7 @@ These are **mirrored** alarms — the source is the source of truth — which is
 | State model scope | **Unified** A&C-style state model for *all* alarms (computed + native) |
 | Interactivity | **Read-only mirror** — display source-reported state; no acking/shelving from ScadaBridge, no command relay, no operator identity captured by ScadaBridge (source-supplied operator user/comment *are* displayed for native alarms) |
 | Binding | Instance declares a `NativeAlarmSource` (connection + source ref); conditions under it are **discovered at runtime**, keyed by source reference |
-| State location | **Site-only**, persisted to SQLite (survives restart/failover); central **queries live** (snapshot + live stream); **no central tables, no central history** |
+| State location | **Site-only**, persisted to SQLite (survives restart/failover); central **queries live** (snapshot + live stream); **no central tables, no central history** (the M9 aggregated live alarm stream — `2026-07-10-aggregated-live-alarm-stream-plan.md` — honors this: a **transient, in-memory** central cache only, nothing persisted) |
 | MxGateway transport | Gateway session-less `StreamAlarms` feed |
 | OPC UA transport | Alarms & Conditions events + `ConditionRefresh` snapshot |
 | Site actor structure | New `NativeAlarmActor` child of `InstanceActor`, peer to computed `AlarmActor`s (Approach 1) |

docs/plans/2026-06-15-stillpending-completion-design.md

@@ -92,7 +92,7 @@ Delivered per `docs/plans/2026-06-18-m7-opcua-mxgateway-ux-design.md` (full scop
 - **T16** — browse type-info (DataType/ValueRank/Writable) + **attribute**-override CSV import (InstanceConfigure InputFile + CLI `instance import-overrides --file`). Native-alarm-source-override CSV import was **deferred** (attribute overrides only).
 - **T17** — Verify-endpoint probe (captures-but-never-trusts an untrusted server cert) + **site-local** cert trust (per-node `CertStoreActor`, DeploymentManager broadcast to **both** site nodes; D6) + Admin-gated cert-management UI.
 
-Small follow-ups logged (not blocking): stamp `SourceNode` on the `SecuredWrite` audit rows (currently NULL); an aggregated **live** alarm stream for the summary page (snapshot + poll today); central-persisted, auditable cert trust (site-local today).
+Small follow-ups logged (not blocking): stamp `SourceNode` on the `SecuredWrite` audit rows (currently NULL); an aggregated **live** alarm stream for the summary page (snapshot + poll today) — *delivered 2026-07-10, `docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`*; central-persisted, auditable cert trust (site-local today).
 
 #### M8 — Transport (T18, T20) — **DELIVERED**
 Delivered both features, with the silent gap #16 folded in:

docs/plans/2026-06-18-m7-opcua-mxgateway-ux-design.md

@@ -32,6 +32,10 @@ from the merged `fix/mxgw-supervisory-write`). M7 does **not** reinvent those
 - **Central alarm store / history / journal** — T13 reads live snapshots; no central alarm
   tables (remains `[PERM]` per `2026-05-29-native-alarms-design.md`). No aggregated live gRPC
   stream for the summary page in v1 (snapshot + poll only).
+  **Delivered 2026-07-10** (`docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`): the
+  aggregated live gRPC stream shipped as a **transient, in-memory** per-site central live cache
+  (site-wide alarm-only `SubscribeSite` stream, seed-then-stream). The `[PERM]` no-central-store
+  rule is unchanged — the cache persists nothing.
 - **Native-alarm ack / shelve / suppress write-back** — read-only by design, unchanged.
 - **CSV bulk import of native-alarm-source overrides** (`InstanceNativeAlarmSourceOverride`) —
   the T16 importer targets *attribute* overrides only; native-alarm-source CSV is a follow-up.
@@ -102,7 +106,9 @@ M7 adds these verbs on that path (all additive, mirroring `BrowseCommands.cs` +
 - **Reuse:** extract DebugView's inline alarm badge/formatter markup into a shared
   `AlarmStateBadges` component consumed by both DebugView and the summary page.
 - **Refresh:** manual button + optional poll timer (mirrors Health dashboard 10 s). No
-  aggregated live stream in v1.
+  aggregated live stream in v1. *(Aggregated live stream delivered 2026-07-10 —
+  `docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`; the poll is now a fallback +
+  `NotReporting` authority behind the transient per-site live cache.)*
 - **Files (indicative):** `Components/Pages/Monitoring/AlarmSummary.razor(.cs)`, a CentralUI
   `IAlarmSummaryService`/impl (fan-out + aggregate), `Components/Shared/AlarmStateBadges.razor`,
   `NavMenu.razor`, Playwright test.

docs/plans/2026-07-08-deferred-work-register.md

@@ -20,7 +20,6 @@ them and are removed from this table when that plan's task lands.
 |---|------|-------------|------------------------|-----------------|
 | 8 | Hash-chain tamper evidence (T1); CLI verify-chain is a no-op stub | audit-log roadmap :12 | v1.x by locked decision; append-only DB roles are the control | Compliance requirement for cryptographic tamper evidence |
 | 9 | Parquet audit archival (T2); endpoint returns 501 | AuditEndpoints.cs:204 | v1.x; 501 + CLI messaging are honest | AuditLog partition volume nears retention ceiling |
-| 10 | Aggregated live alarm stream for Alarm Summary | m7 design :252 | Snapshot fan-out acceptable at current instance counts | Alarm Summary latency complaints or >~50 instances/site |
 | 11 | Central-persisted OPC UA cert-trust audit | m7 follow-ups | Broadcast-to-both-nodes covers HA | Governance/audit requirement for trust decisions |
 | 12 | Native-alarm-source-override CSV import — **Central UI `InstanceConfigure` upload affordance only** (CLI + Management API + parser shipped 2026-07-10, see Resolved) | m7 follow-ups | CLI/API path closes the operator parity gap; the Blazor upload button is polish | First request to bulk-import native sources from the UI rather than the CLI |
 | 17 | Unified notifications+site-calls outbox page | stillpending :118 | Explicit M9 decision to keep two pages | Operator confusion reports |
@@ -33,6 +32,7 @@ Rows removed from the Deferred table above once confirmed shipped. Kept here for
 
 | # | Item | Resolution |
 |---|------|-----------|
+| 10 | Aggregated live alarm stream for Alarm Summary | Shipped 2026-07-10 (`docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`): a **transient, in-memory** per-site central live alarm cache (`ISiteAlarmLiveCache`/`SiteAlarmLiveCacheService` + per-site `SiteAlarmAggregatorActor`) fed by a new site-wide, alarm-only `SubscribeSite` gRPC stream (`SiteStreamManager.SubscribeSiteAlarms`), seed-then-stream with dedup + NodeA↔NodeB re-seed + periodic reconcile. Alarm Summary is now live-cache-driven (`AlarmSummaryService.BuildFromLiveAlarms`) with the 15s poll retained as fallback + `NotReporting` authority. Honors the `[PERM]` no-central-store rule — nothing persisted (no EF table/migration). Options on `CommunicationOptions` (eagerly validated) + two `ScadaBridgeTelemetry` signals. |
 | 7 | SecuredWrite audit rows leave SourceNode NULL | Resolved (PLAN-07): `ManagementActor.EmitSecuredWriteAuditAsync` routes through `ICentralAuditWriter`, which stamps `SourceNode` (`central-a`/`central-b`) from `INodeIdentityProvider`. |
 | 12 (CLI/API) | Native-alarm-source-override CSV import | Shipped 2026-07-10: shared `CsvLineSplitter`, `NativeAlarmSourceOverrideCsvParser`, bulk all-or-nothing `SetInstanceNativeAlarmSourceOverridesCommand` + ManagementActor handler (Deployer-gated), CLI `instance native-alarm-source import --file`, parser/CLI/handler tests. **UI upload affordance still pending — see row 12 above.** |
 | 13 | WaitForAttribute quality-gated ("Good"-only) mode | Already implemented (Commons `WaitForAttribute.RequireGoodQuality`, enforced in `InstanceActor`, threaded through `ScriptRuntimeContext`, tested in `InstanceActorWaitForAttributeTests`). Stale "planned enhancement" doc line corrected 2026-07-10. |

docs/requirements/Component-CentralUI.md

@@ -187,10 +187,11 @@ Per-leaf alarm rendering (leaf nodes are individual conditions for native alarms
 
 ### Alarm Summary (Deployment Role)
 - A dedicated operator **Alarm Summary** page (`/monitoring/alarms`, `RequireDeployment`) gives a **cross-instance, read-only** roll-up of live alarm state at a site — the operator-facing complement to the per-instance Debug View.
-- **Data path** — no new site-side code and no central alarm store. The page selects a site, queries its deployed instances, then fans out the existing per-instance `DebugViewSnapshot` Ask **concurrently** (capped with a `SemaphoreSlim`) and aggregates the returned `AlarmStates` client-side. The fan-out is **partial-results tolerant**: instances that time out are listed as "not reporting" while the rest still render.
+- **Data path** — no new site-side code and no central alarm store. The page selects a site, queries its deployed instances, then fans out the existing per-instance `DebugViewSnapshot` Ask **concurrently** (capped with a `SemaphoreSlim`) and aggregates the returned `AlarmStates` client-side. The fan-out is **partial-results tolerant**: instances that time out are listed as "not reporting" while the rest still render. This snapshot fan-out now doubles as the **seed** for a near-real-time live feed (see **Live updates** below) rather than the sole refresh mechanism.
+- **Live updates** — the page is driven by a **transient, per-site central live alarm cache** (`ISiteAlarmLiveCache`, owned by the Communication component; see [Component-Communication](Component-Communication.md)). On site select the page subscribes to the cache; the cache runs one shared, reference-counted per-site aggregator that **seeds** from the snapshot fan-out and then stays warm on a single **site-wide, alarm-only** `SubscribeSite` gRPC stream (seed-then-stream, dedup by `(InstanceUniqueName, AlarmName, SourceReference)`). Applied deltas raise an in-process change event (mirroring `IDeploymentStatusNotifier`) that the Blazor circuit pushes to the browser via `StateHasChanged()` — no new SignalR hub. `AlarmSummaryService.BuildFromLiveAlarms` rebuilds the roll-up + rows from the cache's current alarm set. The cache is **purely in-memory on the active central node** — there is still **no persisted central alarm store**; on a NodeA↔NodeB failover the new active node re-seeds from scratch.
 - **View** — roll-up tiles (total active, worst severity, unacked count, per-`AlarmKind` counts) plus a flat, sortable, filterable table. Filters cover instance, `AlarmKind` (Computed / NativeOpcUa / NativeMxAccess), state, acked/unacked, severity threshold, and name search.
 - **Read-only** — there are no ack / shelve / suppress controls (native alarms remain read-only by design).
-- **Refresh** — manual refresh button plus an optional poll timer (mirroring the Health dashboard); there is no aggregated live alarm stream in this release (snapshot + poll only — logged as a follow-up).
+- **Refresh** — manual refresh button plus the 15s poll timer (mirroring the Health dashboard), now retained as a **fallback + `NotReporting` authority** behind the live cache: when the cache reports `IsLive`, the page renders live-cache state; when a stream is unhealthy or a site has not yet seeded, the poll keeps the page fresh so a stream failure never blanks it. (Aggregated live stream **delivered 2026-07-10** — see `docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`.)
 - **Reuse** — the alarm badge/formatter markup is factored out of Debug View into a shared `AlarmStateBadges` component consumed by both Debug View and this page.
 
 ### Parked Message Management (Deployment Role)

docs/requirements/Component-Communication.md

@@ -67,6 +67,17 @@ Both central and site clusters. Each side has communication actors that handle m
 - **Accepted limitation (central-side session locality):** debug sessions are process-local state on the central node hosting the `DebugStreamBridgeActor`. A central **restart or failover drops all active sessions** with no `OnStreamTerminated` signal to the operator — the engineer simply re-establishes the debug session from the UI. Debug streaming is an interactive, transient diagnostic aid, so this is an accepted trade-off rather than a durability gap (arch review 02, U7).
 - **Backpressure is lossy-by-design and now observable:** the per-session `Channel<SiteStreamEvent>` (bounded 1000, `DropOldest`) silently evicts the oldest event when a slow consumer falls behind. The eviction is counted via the channel's `itemDropped` callback and logged at Warning (first eviction, then every 500th) so real event loss on a debug stream is visible instead of silent.
 
+### 6.1 Aggregated Live Alarm Stream (Site → Central)
+
+Delivered 2026-07-10 (`docs/plans/2026-07-10-aggregated-live-alarm-stream-plan.md`) for the operator Alarm Summary page (Central UI #9). Where §6 streams **one instance** for the interactive Debug View, this feeds a **transient, per-site central live alarm cache** so the Alarm Summary reflects alarm transitions in near-real-time instead of re-polling the whole site every 15s.
+
+- **Site-wide, alarm-only stream**: a single `SubscribeSite` gRPC stream per site carries `AlarmStateChanged` events for **all** instances (attribute events are dropped — the summary never shows them, and attributes are far higher-volume). On the site this reuses the existing `SiteStreamManager` broadcast hub via `SiteStreamManager.SubscribeSiteAlarms(...)` (same wiring as the per-instance `Subscribe`, minus the `InstanceUniqueName` filter and filtered to alarms). `StreamRelayActor` is reused unchanged, so placeholder rows (`is_configured_placeholder`) are still dropped at the relay.
+- **Central live cache** (`ISiteAlarmLiveCache`, singleton `SiteAlarmLiveCacheService`): a DI singleton on the active central node. For each site with ≥1 active viewer it runs ONE shared, **reference-counted** per-site aggregator (`SiteAlarmAggregatorActor`); the first `Subscribe(siteId, onChanged)` starts it, the last subscriber leaving stops it after a short **linger** to avoid re-seed thrash. `GetCurrentAlarms(siteId)` returns the current immutable snapshot; `IsLive(siteId)` reports whether the aggregator has seeded and published at least once.
+- **Seed-then-stream** (copied from `DebugStreamBridgeActor` ordering): open the `SubscribeSite` stream first (buffer live deltas), run the snapshot fan-out once via the existing `DebugViewSnapshot` path (bounded by `LiveAlarmCacheSeedConcurrency`), flush the buffer with **dedup by `(InstanceUniqueName, AlarmName, SourceReference)`**, then live pass-through. Placeholders are seeded from the snapshot and never expected on the live stream.
+- **Failover & drift**: NodeA↔NodeB reconnect (client via `SiteStreamGrpcClient.SubscribeSiteAsync`, factory endpoint failover) re-seeds rather than serving stale; a periodic **reconcile snapshot** (default 60s) corrects any missed enable/disable so the cache can't drift indefinitely. `[PERM]` (`docs/plans/2026-05-29-native-alarms-design.md`): the cache is **purely in-memory** — no EF entity/table/migration, no persisted central alarm store — so a new active node simply re-seeds from scratch.
+- **Options** (`Communication` section, `CommunicationOptions`; eagerly validated by `CommunicationOptionsValidator` / `ValidateOnStart`): `LiveAlarmCacheLinger` (default 30s), `LiveAlarmCacheReconcileInterval` (default 60s), `LiveAlarmCacheSeedConcurrency` (default 8), `LiveAlarmCacheMaxSubscribersPerSite` (default 200).
+- **Telemetry** (`ScadaBridgeTelemetry` meter): observable gauge `scadabridge.site.alarm_cache.aggregators.active` (running per-site aggregators) and counter `scadabridge.site.alarm_cache.reconnects` (site-wide stream reconnects — a NodeA↔NodeB flip or reconcile-driven reopen; a sustained climb signals a flapping site link).
+
 #### Site-Side gRPC Streaming Components
 
 - **SiteStreamGrpcServer**: gRPC service (`SiteStreamService.SiteStreamServiceBase`) hosted on each site node via Kestrel HTTP/2 on a dedicated port (default 8083). Implements the `SubscribeInstance` RPC. For each subscription, creates a `StreamRelayActor` that subscribes to `SiteStreamManager`, bridges events through a `Channel<SiteStreamEvent>` to the gRPC response stream. Tracks active subscriptions by `correlation_id` — duplicate IDs cancel the old stream. Enforces a max concurrent stream limit (default 100). Rejects streams with `StatusCode.Unavailable` before the actor system is ready.
@@ -84,13 +95,14 @@ Both central and site clusters. Each side has communication actors that handle m
 
 The streaming protocol is defined in `sitestream.proto` (`src/ZB.MOM.WW.ScadaBridge.Communication/Protos/sitestream.proto`):
 
-- **Service**: `SiteStreamService` — hosted on each site node by `SiteStreamGrpcServer` — exposes five RPCs. One is the original real-time **server-streaming** subscription; the other four are **unary request/response** calls added by the Audit Log (#23) and Site Call Audit (#22) components. A unary call is request/response and is distinct from the command/control ClusterClient channel — gRPC on this service is no longer real-time-stream-only:
+- **Service**: `SiteStreamService` — hosted on each site node by `SiteStreamGrpcServer` — exposes six RPCs. Two are real-time **server-streaming** subscriptions (`SubscribeInstance`, `SubscribeSite`); the other four are **unary request/response** calls added by the Audit Log (#23) and Site Call Audit (#22) components. A unary call is request/response and is distinct from the command/control ClusterClient channel — gRPC on this service is no longer real-time-stream-only:
-  - `SubscribeInstance(InstanceStreamRequest) returns (stream SiteStreamEvent)` — the real-time debug stream (§6); the only server-streaming RPC.
+  - `SubscribeInstance(InstanceStreamRequest) returns (stream SiteStreamEvent)` — the per-instance real-time debug stream (§6).
+  - `SubscribeSite(SiteStreamRequest) returns (stream SiteStreamEvent)` — the **site-wide, alarm-only** aggregated stream (§6.1) added for the operator Alarm Summary live cache. Additive (new RPC + new `SiteStreamRequest { correlation_id }` message; no field renumbering). The server handler mirrors `SubscribeInstance` — same bounded `Channel(1000, DropOldest)`, `GrpcMaxConcurrentStreams`/`GrpcMaxStreamLifetime` limits, `SiteConnectionOpened/Closed` telemetry, and `StreamRelayActor` mapping — but subscribes via `SiteStreamManager.SubscribeSiteAlarms` (all instances, `AlarmStateChanged` only; attribute events dropped, no per-instance filter).
   - `IngestAuditEvents(AuditEventBatch) returns (IngestAck)` — central-side **ingest** receiving surface for Audit Log (#23) telemetry; routes the batch to the central `AuditLogIngestActor` proxy and returns the accepted `EventId`s. (The production *push* path is still ClusterClient via `ClusterClientSiteAuditClient`; this RPC is the gRPC-receiving counterpart.)
   - `IngestCachedTelemetry(CachedTelemetryBatch) returns (IngestAck)` — ingest receiving surface for the combined cached-call telemetry packet (audit row + `SiteCalls` operational upsert written in one transaction).
   - `PullAuditEvents(PullAuditEventsRequest) returns (PullAuditEventsResponse)` — central→site **reconciliation pull** for the Audit Log self-heal feed; the site serves `Pending`/`Forwarded` rows from its `ISiteAuditQueue`.
   - `PullSiteCalls(PullSiteCallsRequest) returns (PullSiteCallsResponse)` — central→site reconciliation pull for the Site Call Audit (#22) self-heal feed; the site serves operation-tracking rows changed since a cursor from its `IOperationTrackingStore`. A separate RPC from `PullAuditEvents` because the tracking store is the operational source of truth, distinct from the site audit queue.
-- **Messages**: `InstanceStreamRequest` (correlation_id, instance_unique_name), `SiteStreamEvent` (correlation_id, oneof event: `AttributeValueUpdate`, `AlarmStateUpdate`); `AuditEventDto`/`AuditEventBatch`/`IngestAck` for ingest; `CachedTelemetryPacket`/`CachedTelemetryBatch` (each packet pairing an `AuditEventDto` with a `SiteCallOperationalDto`); `PullAuditEventsRequest`/`PullAuditEventsResponse` and `PullSiteCallsRequest`/`PullSiteCallsResponse` (each request carries `since_utc` + `batch_size`; each response carries `more_available` to signal a saturated batch).
+- **Messages**: `InstanceStreamRequest` (correlation_id, instance_unique_name), `SiteStreamRequest` (correlation_id only — no instance name; drives the site-wide `SubscribeSite` stream), `SiteStreamEvent` (correlation_id, oneof event: `AttributeValueUpdate`, `AlarmStateUpdate`); `AuditEventDto`/`AuditEventBatch`/`IngestAck` for ingest; `CachedTelemetryPacket`/`CachedTelemetryBatch` (each packet pairing an `AuditEventDto` with a `SiteCallOperationalDto`); `PullAuditEventsRequest`/`PullAuditEventsResponse` and `PullSiteCallsRequest`/`PullSiteCallsResponse` (each request carries `since_utc` + `batch_size`; each response carries `more_available` to signal a saturated batch).
 - The `oneof event` pattern is extensible — future event types (health metrics, connection state changes) are added as new fields without breaking existing consumers.
 - Proto field numbers are never reused; new RPCs and message fields are appended additively. Old clients ignore unknown `oneof` variants.