docs(index): refresh ScadaBridge/HistorianGateway rows; record HG 2026-10-16 diagnostics + Int1 milestones

.claude/skills/sister-project-history/historiangateway.md

@@ -33,3 +33,37 @@
 - **2026-10-13 explicit live-test opt-in #47 merged (PR #49, main `a075a80`, tested `cf67a200`).** External startup/reads require HISTORIAN_LIVE_READ_TESTS=true; mutations also require HISTORIAN_LIVE_WRITE_TESTS=true, preserving sandbox/host/specialized gates. SDK event-read registration submits full CM_EVENT EnsureTags metadata and requires both; SQL reads remain read-only. Shared helper stays within standalone SDK; whitelist offline runner added. Offline1,949pass/157skip/0fail/0warnings, isolatedgate/auth24+fixture8+runner1; independent review clear, hosted969 passed, merged tree matches tested source. #47 closed; primary Desktop checkout fast-forwarded clean. No live calls/writes or production source changes. Earlier hosted keepalive failures retained separately #50; concrete survival assertion gap filed #51 (approval pending), with no historical causality claim.
 
 - 2026-10-13: #51 completed via PR #52, merged `5250e606754c00ca4e5557af23dd8e9a9a4ceb6b`, tested-tree equality verified. Three simultaneous reacquired leases now prove all original keepalive sessions survive/restored. Both eviction/omitted-restoration mutations fail both pool variants; production files byte-restored. 133 contract and 1,130 full offline server tests passed (58 skipped); hosted run974 passed. Test-only; no live calls. #50 historical CI cause remains open.
+
+- **2026-10-16 local diagnostics implementation on `codex/operational-diagnostics` (independently reviewed; unmerged).** Added `HistorianStatus.GetOperationalDiagnostics` and typed .NET wrapper; four curated services / 22 RPCs. Reads existing local redundancy/outbox singletons without Historian calls. Snapshot observations include draining and last completed flush; optional fields distinguish unavailable/disabled from zero. Verified read API key required even in Disabled mode; safe fixed error tokens and per-key concurrency enforced. Focused SDK22, descriptors18, provider/mapper13, service/auth/DI95, client30 tests passed. Full Release verification: 2,004 passed / 157 skipped / 0 failed, zero warnings; independent branch review passed with no findings; no package publication or deployment. Remaining write/protocol gaps stay open.
+
+
+### 2026-10-16 — historical Int1 implementation milestone (unmerged)
+
+Stacked branch `codex/historical-int1`, implementation `c136088`: statically
+evidenced one-byte Int1 historical encoding with checked integer conversion and
+11 new unit cases. Independent review found no Critical/Important issues; public
+XML wording is a deferred minor. Full offline Release suite: 2015 passed, 161
+skipped, zero failed; build zero warnings/errors. Disposable live Int1 and Float
+write acknowledgements succeeded, but native StartQuery and independent SQL
+History readback timed out for both. An existing system-tag read timed out too.
+The persistence gap remains open; cleanup/absence checks and the prefix audit
+passed. No server restart/configuration changes, merge, push or deployment.
+Proposed next historical-string design uses a dedicated RPC and physically
+isolated durable string partitions for both file storage and production FasterLog
+to prevent older software from misreading/discarding queued strings.
+
+Follow-up read-only evidence (`79e8417`, `f65f406`): ordinary SQL and Historian
+status respond, while a narrow system-tag History query times out through both
+SQL and native retrieval; configured SQL credentials lack service-diagnostics
+permission. Current gRPC event mode decodes to 0x00030101, already without
+0x400; that clearing hypothesis only remains meaningful for WCF's 0x501 path.
+String conversion IL rechecked; non-ASCII code-page conversion, character-unit
+counts and native truncation remain explicit implementation/validation work.
+
+User steering (2026-10-16): pursue native Historian gRPC, not new SQL work.
+Removed the newly added SQL historical readback variants/helper; Int1 lifecycle
+validation and the proposed string design now use native gRPC only. No SQL
+fallback/filter expansion or SQL readback gate is pursued. Existing shipped SQL
+features were not removed. Targeted Release verification: 24 passed, 6 live
+skips, zero failed. Native gRPC StartQuery timeout remains an unresolved blocker
+for persistence evidence.