docs(index): record OtOpcUa historian fixes and live measurement

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

@@ -328,3 +328,17 @@ AddRoute of the dev Mac (`oee-tagdump-mac`, `10.181.206.245.1.1`) on the two tes
   Follow-ups #695–#698.
   - **ScadaBridge impact:** none — it issues no HistoryRead. (#697, backend outage answered `BadHistoryOperationUnsupported`,
     should check consumer handling before its status change.)
+
+- **2026-10-13 #695–#698 historian follow-ups (pushed `97668d26`, PR #699; awaiting merge).** Gateway crowding reads spend remaining learned-ceiling room before refusal,
+  and reverse reads retry with room for the observed pre-window cluster (#695). Future AtTime queries use a bounded future
+  probe before starting near now, retaining stored future samples, requested timestamps and Uncertain status (#696 item 1;
+  items 2/3 remain open). Transport outages now answer **BadNoCommunication** across all HistoryRead arms on Gateway,
+  SqlServer and QuestDB; unsupported operations remain unsupported and cancellation remains BadTimeout (#697).
+  Raw/Modified/AtTime scalar values now match the node DataType, with per-sample BadTypeMismatch on conversion failure;
+  arrays and Processed aggregate types retain their own values (#698).
+  - **ScadaBridge impact:** none — source/tests contain no HistoryRead consumer.
+  - **#653 live remeasurement:** commissioned and revoked a temporary read-only key. Five calls each: nonexistent-tag
+    Raw/Aggregate ~30.6 s, direct Gateway AtTime ~61.3 s, metadata failure 41–89 ms; SysTimeSec operations 48–309 ms.
+    Delay confirmed; metadata pre-check plus short negative cache recommended, implementation remains open.
+    #694 item 3 remains blocked on historiangw#27. Evidence: OtOpcUa `docs/plans/2026-10-13-historian-695-698-results.md`.
+  - **Verification:** full solution 14,581 passed / 609 skipped / 0 failed across 62 suites; independent review found no important defects.