fix(runtime): Primary verdict published from host start, cache boot never adopts malformed bytes, strict drain-gate predicate, HostAbortedException passthrough, seed only Up members

Review R1:
- M1 (#609): DriverHostActor.StopChild releases the instance's resilience state before evicting the hub.
- m2 (#597): DriverHostActor publishes ShouldServiceAsPrimary() to IDriverPrimaryRoleSource at start and on
  cluster membership changes (deduped), so the native-ack gate denies in a pair's boot window.
- m4 (#601): ApplyCachedArtifact returns false on empty/malformed bytes; the cached revision is not adopted,
  Direct mode goes Stale (no RUNNING FROM CACHE), FetchAndCache lands Steady-with-no-revision and a
  re-dispatch of the same revision really applies.
- m3 (#603): LocalDbReplicationPolicy splits into CapturesChanges (PeerAddress||ApiKey, registration) and
  SharesRowsWithPeer (ApiKey && (PeerAddress||SyncListenPort>0), alarm drain gate).
- m5 (#618): Program.cs catch-all filters HostAbortedException (design-time tooling).
- m6 (Cluster-002): ClusterRoleInfo seeds only Up/WeaklyUp members.

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe

docs/AlarmHistorian.md

@@ -93,6 +93,16 @@ Two postures are deliberate:
 - **Unset (the default) means drain.** So does an unpublished view. A deployment
   that runs no redundancy never publishes a role, and defaulting closed would
   silently stop its alarm history forever.
+- **Only a shared queue is gated.** Standing down is safe only because a peer
+  holds the same rows, so the gate applies only when
+  `LocalDbReplicationPolicy.SharesRowsWithPeer` holds:
+  `LocalDb:Replication:ApiKey` **AND** (`LocalDb:Replication:PeerAddress` **OR**
+  `LocalDb:SyncListenPort > 0`) — an authenticated sync path in either
+  direction. Any other node always drains its own queue. This is deliberately
+  stricter than the table-registration predicate (`PeerAddress` OR `ApiKey`):
+  a key with no dial and no listener (e.g. a fleet-wide secret on an unpaired
+  node) captures changes but shares them with nobody, and gating it would park
+  its events behind a Primary that does not hold them (review R1 m3).
 - **A gate that throws means "not now", never permission.** Draining on a gate
   fault would put a pair into dual delivery exactly when its redundancy signal is
   sick.

docs/Configuration.md

@@ -218,7 +218,7 @@ See the [ClusterClient→gRPC migration design](plans/2026-08-06-clusterclient-t
 | `GrpcListenPort` | int | `0` | Dedicated **h2c-only** Kestrel port for the artifact gRPC service. `0` = disabled (nothing bound). Must differ from the main HTTP port and from `LocalDb:SyncListenPort` (h2c cannot share a cleartext HTTP/1 port). Mapped only on admin-role nodes. |
 | `ApiKey` | string | `""` | Shared bearer key the serve-side interceptor checks (constant-time, **fail-closed**: an unset key rejects every call). **Supply via env `ConfigServe__ApiKey` — never commit.** |
 
-**It is a dark switch; the serve side is always wired.** Central maps the `DeploymentArtifactService` behind the `ConfigServeAuthInterceptor` (path-scoped, `FixedTimeEquals`, fail-closed) whenever `ConfigServe:GrpcListenPort > 0`, in both modes — so flipping a node to `FetchAndCache` is a config change, not a redeploy. A `FetchAndCache` node that cannot fetch (all endpoints down, `NotFound`, SHA mismatch) **fails the apply and keeps last-known-good** — a null fetch is "no answer," never an empty configuration (the [#485](plans/2026-07-15-v3-batch4-address-space-plan.md) contract). At boot it restores served state from the LocalDb pointer with no SQL read; an empty or unreadable cache lands Steady-with-no-revision (the first dispatch fetches), never Stale.
+**It is a dark switch; the serve side is always wired.** Central maps the `DeploymentArtifactService` behind the `ConfigServeAuthInterceptor` (path-scoped, `FixedTimeEquals`, fail-closed) whenever `ConfigServe:GrpcListenPort > 0`, in both modes — so flipping a node to `FetchAndCache` is a config change, not a redeploy. A `FetchAndCache` node that cannot fetch (all endpoints down, `NotFound`, SHA mismatch) **fails the apply and keeps last-known-good** — a null fetch is "no answer," never an empty configuration (the [#485](plans/2026-07-15-v3-batch4-address-space-plan.md) contract). At boot it restores served state from the LocalDb pointer with no SQL read; an empty or unreadable cache — including a cached row whose bytes are malformed (review R1 m4) — lands Steady-with-no-revision (the first dispatch fetches, even of the same revision), never Stale.
 
 **The listener is dedicated h2c and coexists with the LocalDb-sync listener.** A fused admin+driver node with **both** `ConfigServe:GrpcListenPort` and `LocalDb:SyncListenPort` set re-binds its existing HTTP surface exactly once and adds both dedicated HTTP/2-only ports on top — see the same Kestrel-takeover caveat under [`LocalDb`](#localdb-pair-local-config-cache--driver-role-only).
 
@@ -431,7 +431,10 @@ replication stays inert until the sync port + peer are set.
 `PeerAddress` **OR** `ApiKey` non-blank — the OR because only the *dialling* half sets `PeerAddress`, so
 keying on it alone would strip change capture from every passive node and leave the pair converging in one
 direction only. `SyncListenPort` is deliberately **not** part of it (a port with no `ApiKey` is fail-closed
-and syncs with nobody). A configured node registers all four tables with `baselineExistingRows: true`, so
+and syncs with nobody). (The alarm-historian **drain gate** uses a stricter predicate on purpose —
+`ApiKey` AND (`PeerAddress` OR `SyncListenPort > 0`), `LocalDbReplicationPolicy.SharesRowsWithPeer` — because
+gating a node that shares its queue with nobody strands its alarm history; see `docs/AlarmHistorian.md`
+§"The drain gate".) A configured node registers all four tables with `baselineExistingRows: true`, so
 turning replication on converges the rows **already in the file** and not merely subsequent writes; an
 unconfigured node **deregisters** them at boot, dropping capture triggers an earlier build installed. ⚠️ The
 sync handshake compares registered-table digests **fail-closed**, so flipping either key is a

docs/Redundancy.md

@@ -526,13 +526,13 @@ Three data-plane surfaces are **Primary-gated** so a warm standby never touches
 
 Before archreview 03/S4 the unknown-role case defaulted to *allow* unconditionally, opening a dual-primary window: a freshly-booted secondary on a multi-node cluster serviced shared-device writes and emitted duplicate fleet-wide alerts for up to the ~10 s `RedundancyStateActor` heartbeat (and indefinitely if the snapshot's NodeId never matched this node). Membership is authoritative much earlier than DPS delivery, so an unknown role on a **multi-driver** cluster now default-**denies**. The driver member count is read live from `Cluster.State.Members` (Up members with the `driver` role); a non-cluster ActorRefProvider yields 0 ⇒ single-node posture. If a snapshot arrives that never mentions this node while a driver peer exists (the 03/S5 identity-mismatch shape), `DriverHostActor` logs a one-time Warning so the silent mismatch is diagnosable.
 
-**What a client sees during the boot window (multi-node, role unknown):** an inbound write is **rejected** (not queued — OT actuation seconds late is a surprise). The reject rides the sanctioned optimistic-write self-correction surface: the node reverts to its prior value with a transient Bad-quality blip and a Part 8 `AuditWriteUpdateEvent`; the client's synchronous write call still returned Good (exactly as any failed device write behaves since the #5 write-outcome self-correction). The rejection reason distinguishes the boot window (`"not primary (role unknown)"`) from a steady-state Secondary (`"not primary"`). Acks are dropped (Warning-logged when role-unknown). The alerts emit is skipped (the Primary peer publishes the single fleet copy). The window closes on the first delivered snapshot.
+**What a client sees during the boot window (multi-node, role unknown):** an inbound write is **rejected** (not queued — OT actuation seconds late is a surprise). The reject rides the sanctioned optimistic-write self-correction surface: the node reverts to its prior value with a transient Bad-quality blip and a Part 8 `AuditWriteUpdateEvent`; the client's synchronous write call still returned Good (exactly as any failed device write behaves since the #5 write-outcome self-correction). The rejection reason distinguishes the boot window (`"not primary (role unknown)"`) from a steady-state Secondary (`"not primary"`). Acks are dropped (Warning-logged when role-unknown) — and since review R1 m2 a native OPC UA Acknowledge is refused up front (`BadInvalidState`) in the same window: `DriverHostActor` publishes its Primary verdict to `IDriverPrimaryRoleSource` (the native-ack gate, and the MQTT Sparkplug primary-host claim) once at start and again on every cluster membership change, not only on redundancy snapshots, so the published verdict denies as soon as a driver peer is Up rather than sitting on the single-node "allow" seed until the first snapshot. The alerts emit is skipped (the Primary peer publishes the single fleet copy). The window closes on the first delivered snapshot.
 
 Under warm/hot redundancy both cluster nodes run `ScriptedAlarmHostActor` and evaluate scripted alarms, keeping each node's address space and engine state warm for instant failover. To avoid duplicate rows on `/alerts` and duplicate historian writes, only the Primary node publishes externally:
 
 - **`alerts` topic emission** — `ScriptedAlarmHostActor` and `DriverHostActor.ForwardNativeAlarm` subscribe to the `redundancy-state` DPS topic and cache the local node's `RedundancyRole`, then gate the cluster `alerts` publish through `PrimaryGatePolicy` (table above). The OPC UA condition-node write and inbound ack/shelve command processing remain **ungated** on both nodes so the secondary is always ready to serve clients after a failover.
 - **`HistorianAdapterActor` historization** — likewise Primary-gated so alarm historization is exactly-once across all alarm sources. The actor subscribes to the `alerts` DPS topic and translates each `AlarmTransitionEvent` → `AlarmHistorianEvent` before enqueuing it on the sink; scripted alarms therefore historize exactly once regardless of cluster size.
-- **The alarm sink's DRAIN** — a second, independent gate on the same decision. The enqueue gate above is not sufficient any more: since Phase 2 the store-and-forward buffer lives in the replicated LocalDb, so the Secondary holds a full copy of the Primary's queued rows and an ungated drain there would re-deliver every event continuously. `LocalDbStoreAndForwardSink` takes a `drainGate` fed from `IRedundancyRoleView` — a singleton `DriverHostActor` publishes its `PrimaryGatePolicy` verdict to, because the drain runs on a timer and cannot receive `RedundancyStateChanged` itself. A gated-off node reports `HistorianDrainState.NotPrimary`. Delivery is **at-least-once across a failover** by design: rows the old Primary delivered just before dying may not have replicated their deletes yet. See [AlarmHistorian.md](AlarmHistorian.md).
+- **The alarm sink's DRAIN** — a second, independent gate on the same decision. The enqueue gate above is not sufficient any more: since Phase 2 the store-and-forward buffer lives in the replicated LocalDb, so the Secondary holds a full copy of the Primary's queued rows and an ungated drain there would re-deliver every event continuously. `LocalDbStoreAndForwardSink` takes a `drainGate` fed from `IRedundancyRoleView` — a singleton `DriverHostActor` publishes its `PrimaryGatePolicy` verdict to, because the drain runs on a timer and cannot receive `RedundancyStateChanged` itself. A gated-off node reports `HistorianDrainState.NotPrimary`. The gate applies only to a node whose queue a peer actually holds — `LocalDbReplicationPolicy.SharesRowsWithPeer`: `LocalDb:Replication:ApiKey` AND (`PeerAddress` OR `LocalDb:SyncListenPort` > 0); any other node always drains (review R1 m3). Delivery is **at-least-once across a failover** by design: rows the old Primary delivered just before dying may not have replicated their deletes yet. See [AlarmHistorian.md](AlarmHistorian.md).
 
 - **Continuous-historization value CAPTURE** (Gitea #537) — a third gate on the same role rule, and the
   one that gates the *opposite* half of its pipeline. Both pair nodes serve the same address space and see
@@ -622,7 +622,10 @@ and [AlarmHistorian.md](AlarmHistorian.md). Phase 1 caches the **deployed-config
 artifact** (chunked). Its job is a single failure mode redundancy does not otherwise cover: a driver
 node restarting into a **central-SQL-Server outage** would come up with no configuration at all. With
 the cache, it **boots from the last artifact it applied** instead, and logs a running-from-cache
-signal.
+signal. A cached artifact whose bytes are empty or malformed is **no answer** (#601): nothing is applied,
+the node does **not** adopt that revision or claim running-from-cache, and it goes **Stale** (retrying the
+ConfigDb) — so a later dispatch of that same revision really applies instead of being acked as already
+current (review R1 m4). A `FetchAndCache` node lands Steady-with-no-revision instead, as for an empty cache.
 
 - **What replicates.** The cache can *optionally* replicate to the node's redundant pair peer over
   the LocalDb library's gRPC sync (HLC-stamped, last-writer-wins). Two tables replicate:

docs/operations/2026-07-20-localdb-pair-replication.md

@@ -92,7 +92,9 @@ Replication has two knobs, both under `LocalDb`:
 > 2026-08-18 `LocalDbSetup.OnReady` installs the change-capture triggers only when the node is
 > configured to replicate — the predicate is **`PeerAddress` OR `ApiKey` non-blank** (the OR because
 > the passive node has no `PeerAddress`; `SyncListenPort` is deliberately not part of it, since a
-> port with no key is fail-closed and syncs with nobody). Consequences at enablement time:
+> port with no key is fail-closed and syncs with nobody). The alarm-historian drain gate uses the
+> stricter `ApiKey` AND (`PeerAddress` OR `SyncListenPort > 0`) — so set the key **and** the port/peer
+> together, or the node keeps draining its own queue. Consequences at enablement time:
 >
 > - A configured node registers with **`baselineExistingRows: true`**, so the rows **already in the
 >   file** are seeded into the row-version ledger at the LWW floor (HLC `0`) and actually travel.