fix(historian): #684 review — Uncertain non-numeric samples do not refuse the Good-value aggregates; real-SQL Uncertain-above-max test

- Average/Minimum/Maximum/Range/*ActualTime refuse (BadAggregateInvalidInputs) only a GOOD
  String/DateTime sample (new GoodNonNumericCount / good_non_numeric_count column); an Uncertain
  one is skipped and makes the min/max family Uncertain, matching the SDK (Average skips it,
  ComputeMinMax flags the uncastable value). Delta keeps its usable-sample refusal.
- ProcessedConformance: an Uncertain value above the Good maximum (pins UncMax/unc_max through
  the real SQL) and an Uncertain String through the real SQL.
- The_uncertain_dataset_is_not_vacuous also proves the min/max STATUS discrimination.

Co-Authored-By: Claude <noreply@anthropic.com>

docs/Historian.md

@@ -1013,6 +1013,10 @@ point (see [Continuation-point paging (Events)](#continuation-point-paging-event
 > - The SDK applies only the Bad half of that rule (its `ComputeMinMax` collects the Uncertain extremes and never reads them) and answers
 >   Good for an Uncertain value beyond the extreme; ours follows Part 13 there — the one remaining per-sample Uncertain difference, pinned
 >   by `SdkAggregateParityTests`.
+> - **Non-numeric samples:** these aggregates now answer `BadAggregateInvalidInputs` only for a **Good** `String`/`DateTime` sample
+>   in the interval. An **Uncertain** one is skipped like any Uncertain value — the interval is served from its Good numeric values
+>   with `UncertainDataSubNormal` (the SDK's Average skips it; its Min/Max flags the value it cannot cast). `Delta` reads usable
+>   samples and still refuses any usable non-numeric one.
 > - `Count` (Good only, #680), `Start`/`End`/`Delta` (usable / any-quality picks) and the time-weighted family (Uncertain time counts as
 >   Good time under `TreatUncertainAsBad = false`, as Part 13 §5.4.3.2 says) are unchanged. The advertised `TreatUncertainAsBad = false`
 >   stays correct: it governs the time-weighted and status calculations; the per-sample aggregates above are defined over Good values
@@ -1075,7 +1079,7 @@ Status and edge rules:
 - An **empty interval** (no samples) ⇒ `BadNoData` — except **`Count`**, which is `0`, Good, when the interval lies inside the tag's data range `[first sample, last sample]` (both edges inclusive, either direction; #680). **Every value aggregate over an interval whose samples are all Bad ⇒ `BadNoData`**; `Count` there is the generic **Bad** (value null).
 - An interval with samples but **no Good numeric value** (only Uncertain / Bad) ⇒ `BadNoData` for `Average`/`Minimum`/`Maximum`/`Range`/`*ActualTime` (#684).
 - `Average` is `Good` when every sample in the bucket is Good, else `UncertainDataSubNormal` (value-based, the SDK's rule). `Minimum`/`Maximum`/`Range`/`*ActualTime` are `UncertainDataSubNormal` when the bucket holds a Bad sample or an Uncertain value beyond the reported Good extreme (Part 13 Tables 57–62; strictly beyond), else `Good` (#684). `Count`'s status is value-based (all Good ⇒ Good, all Bad ⇒ Bad, else Uncertain); `Start`/`End` carry the raw sample's own status; `Delta` is Good unless the interval's first or last sample is not usable (then Uncertain) — #680.
-- `Count`, `Start`, `End` accept any value kind; the other aggregates (and `Delta`) on a bucket that holds a usable `String`/`DateTime` sample ⇒ `BadAggregateInvalidInputs` for that interval.
+- `Count`, `Start`, `End` accept any value kind. `Average`/`Minimum`/`Maximum`/`Range`/`*ActualTime` on a bucket that holds a **Good** `String`/`DateTime` sample ⇒ `BadAggregateInvalidInputs` for that interval; an Uncertain one is skipped and makes `Minimum`/`Maximum`/`Range`/`*ActualTime` `UncertainDataSubNormal` (#684). `Delta` is refused by any usable non-numeric sample.
 - `PercentGood` / `PercentBad` are **duration-based since #680** — see [Time-weighted aggregates](#time-weighted-aggregates-part-13-671).
 - Everything except `Count` and `Start`/`End` is a `double`; `Int64` samples aggregate as doubles and `Boolean` as 0/1.