fix(calculation): read cache carries real input status + timestamps

archreview/plans/R3-02-stale-good-family-plan.md

@@ -758,3 +758,15 @@ test could only pass once the production change landed.
 - `TagState.LastPublishedBad` (two-state) became `HasPublished` + `LastPublishedStatus` (uint), which is
   what lets a Bad→different-Bad transition republish and what makes `ReadAsync` agree with the
   subscriber. The evaluator is still handed bare values here — T14 hands it the snapshots.
+
+### T14 — `CalculationEvaluator` snapshot overload
+
+- RED: `--filter "…CalculationEvaluatorTests"` ⇒ **build failure**, `CS1503: cannot convert from
+  'Dictionary<string, DataValueSnapshot>' to 'IReadOnlyDictionary<string, object?>'` (×3) — no snapshot
+  overload existed.
+- GREEN: `Driver.Calculation.Tests` 64/64.
+- `BuildReadCache` is **deleted**, not fixed: the snapshots now pass straight through as the read cache.
+  The value-only overload survives (tests use it) but is now the one that fabricates Good, and its
+  xmldoc says so and points at the snapshot overload.
+- Docs: `docs/drivers/Calculation.md` gains an "Input quality" section (the policy table + the
+  behaviour change for null-tolerant scripts) and the dedup bullet now says **(value, status)**.

archreview/plans/R3-02-stale-good-family-plan.md.tasks.json

@@ -102,7 +102,7 @@
     {
       "id": "T14",
       "subject": "CalculationEvaluator snapshot overload: read cache carries real input status + timestamps; passthrough fast path on snapshots",
-      "status": "pending",
+      "status": "done",
       "blockedBy": [
         "T13"
       ]