docs(historian): #691.2 forward native reads now share the 100k-interval BucketPlan cap

CLAUDE.md

@@ -1365,7 +1365,7 @@ historian tagname, which is the tag's driver `FullName`.
 The server dispatches all OPC UA HistoryRead to the registered `IHistorianDataSource` — the
 `GatewayHistorianDataSource` read client when enabled, else the `NullHistorianDataSource` default
 (historized nodes return `GoodNoData` for Raw/AtTime — Processed is `BadAggregateNotSupported` since #682). Supported variants: Raw (⚠️ #687, client-visible: Gateway raw reads no longer return AVEVA's synthetic start-boundary row — asked from 1 ms early (epoch-floored) with `NumValuesPerNode + 16` rows (unclamped; 0 ⇒ `int.MaxValue`) and filtered by timestamp — so an empty window is `GoodNoData`, not a fabricated value at StartTime; the forward end is now exclusive (a point read inclusive); pre-window rows that crowd the budget trigger ONE re-read with room for them, else `BadTooManyOperations`; `ReturnBounds` is ignored on every backend; ⚠️ #690: a Gateway Bad row — a stored NULL, which histsdk sends as value 0 — now reads value **null** + Bad on Raw and AtTime, as on the SQL backends; ⚠️ #691.3: a strict gateway (`AllowStreamingBeyondCeiling=false`) that refuses a raw budget is re-asked ONCE at the ceiling its refusal names — raw and per-sample reads alike; the ceiling is then remembered per data source (`GatewayRowCeiling`: refusals count as gateway errors), re-learned from a refusal when lowered, and re-probed once at the full budget when a ceiling-bounded read comes back full (raised / streaming) — so an uncapped (`NumValuesPerNode = 0`) read of a small window is served; a ceiling-bounded stream that is not provably complete is `BadTooManyOperations`, never a truncated answer), Processed
-(backend-dependent: SqlServer/QuestDb serve seventeen; Gateway twelve = `GatewayHistorianDataSource.ServedAggregates` — ⚠️ #681, client-visible: the ten per-sample ones (Average, Count, Min/Max, Range, Start/End/Delta, Min/MaxActualTime) are evaluated from RAW gateway reads by the shared `Sql.Common` evaluator — identical to the SQL backends, Calculated bits, interval-start stamps, #677 reverse; Min/Max are no longer AVEVA modes, the read moves every raw sample of the window (a month of 1 Hz ⇒ `BadTooManyOperations` at the default `MaxTimeWeightedRawRows` cap), and every gateway stream is consumed to completion (an abandoned one makes the gateway evict its shared historian session) — plus TimeAverage/Total via AVEVA modes (interval-start stamped + Calculated; ⚠️ #685: AVEVA's extra pre-window row is dropped ⇒ one row per interval in `[Start, End)`, and an Uncertain (opc 64) interval keeps its value as `UncertainDataSubNormal` — AVEVA's TWA excludes NULL-gap time where the SQL backends bridge it; per-interval values still need gateway fix historiangw#27; ⚠️ #691.2: native reads use the SQL backends' grid in both directions via forward requests only — a REVERSE read (refused by the gateway before) is anchored at its later time (#677), and the clipped interval (earliest reverse, LATEST forward — which used to be averaged past EndTime) is its own exact-span read marked Partial unless Bad; an interval wider than the window is sent as the window, interval 0 as one interval; until historiangw#27 lands both directions return Good-status wrong values); the other time-weighted five stay `BadAggregateNotSupported` because the gateway has no prior-sample read for Part 13 bounds; `docs/Historian.md` §Aggregate set), and AtTime over historized variable nodes; Events over
+(backend-dependent: SqlServer/QuestDb serve seventeen; Gateway twelve = `GatewayHistorianDataSource.ServedAggregates` — ⚠️ #681, client-visible: the ten per-sample ones (Average, Count, Min/Max, Range, Start/End/Delta, Min/MaxActualTime) are evaluated from RAW gateway reads by the shared `Sql.Common` evaluator — identical to the SQL backends, Calculated bits, interval-start stamps, #677 reverse; Min/Max are no longer AVEVA modes, the read moves every raw sample of the window (a month of 1 Hz ⇒ `BadTooManyOperations` at the default `MaxTimeWeightedRawRows` cap), and every gateway stream is consumed to completion (an abandoned one makes the gateway evict its shared historian session) — plus TimeAverage/Total via AVEVA modes (interval-start stamped + Calculated; ⚠️ #685: AVEVA's extra pre-window row is dropped ⇒ one row per interval in `[Start, End)`, and an Uncertain (opc 64) interval keeps its value as `UncertainDataSubNormal` — AVEVA's TWA excludes NULL-gap time where the SQL backends bridge it; per-interval values still need gateway fix historiangw#27; ⚠️ #691.2: native reads use the SQL backends' grid in both directions via forward requests only — a REVERSE read (refused by the gateway before) is anchored at its later time (#677), and the clipped interval (earliest reverse, LATEST forward — which used to be averaged past EndTime) is its own exact-span read marked Partial unless Bad; an interval wider than the window is sent as the window, interval 0 as one interval; more than 100,000 intervals is refused up front (`BadHistoryOperationUnsupported`, as on the SQL backends — forward used to be served up to the gateway's 1,000,000); until historiangw#27 lands both directions return Good-status wrong values); the other time-weighted five stay `BadAggregateNotSupported` because the gateway has no prior-sample read for Part 13 bounds; `docs/Historian.md` §Aggregate set), and AtTime over historized variable nodes; Events over
 alarm-owning equipment-folder event-notifier nodes. Reads are ungated (served from any redundancy node);
 authorization uses the standard `AccessLevels.HistoryRead` bit set at materialization.
 

docs/Historian.md

@@ -903,6 +903,10 @@ gateway refuses `start > end` and `interval <= 0`):
   the **Partial** bit unless Bad (Part 13 §5.3.3.2 Case 3, as the SQL backends' time-weighted aggregates — which also mark the intervals
   the tag's data starts/ends inside; AVEVA's rows carry no data range, so that is not reproduced). Rows are otherwise mapped as before
   (#685). An interval AVEVA answers no row for is absent (the SQL backends answer it `BadNoData`).
+- ⚠️ **Interval cap (client-visible):** forward native reads now go through `BucketPlan` too, so a window of more than 100,000
+  intervals (e.g. 1 s over 2 days) is refused up front with `BadHistoryOperationUnsupported`, as on the SQL backends — it used to be
+  served up to the gateway's own `MaxAggregateIntervals` (1,000,000). Not counted as a backend failure. A clipped interval shorter than
+  1 ms (a sub-ms window end) is sent as a sub-ms interval request; re-check it in the post-historiangw#27 live leg.
 - ⚠️ **Until historiangw#27 is fixed, native values are wrong in BOTH directions with a Good status:** AVEVA answers one row per request
   (the whole span's value), which lands on that request's first interval as a Good, Calculated value while the other intervals are
   absent. Pinned against a native-mode fake only — re-run the forward and reverse native legs live once the gateway is fixed. Since #681 every native bucket is stamped with its interval **start**