fix(mqtt/sparkplug): initial push on subscribe + BadNoCommunication on connection loss

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

@@ -618,3 +618,20 @@ test could only pass once the production change landed.
 - The event fires inside the existing `State == Connected` guard in `OnDisconnectedAsync`, which is
   what makes "not on an initial-connect failure" and "not on dispose" true by construction rather
   than by a second condition — `DisposeAsync` sets `Disposed` before tearing the client down.
+
+### T4 — Sparkplug ingestor: initial push + connection-loss stale
+
+- RED: `--filter "…SparkplugIngestorRecoveryTests"` ⇒ **build failure**, `CS1061: 'SparkplugIngestor'
+  does not contain a definition for 'OnConnectionLost'` (×2).
+- GREEN: 6/6. Full `Driver.Mqtt.Tests`: 803/803.
+- ⚠️ **Deviation from the plan's test rationale (recorded, not silently accepted):** the plan asks for
+  the identical-DBIRTH-replay assertion as this seam's vacuity guard. It is present, but **it is not a
+  falsifier here** — Sparkplug ingestion has no unchanged-value suppression at all (births/data
+  publish directly, never through `Deliver`), so that replay was already raised Good before the
+  change. That is now asserted explicitly by an added control,
+  `An_identical_birth_replay_is_raised_even_without_a_preceding_stale`, and the suite header says so.
+  The load-bearing assertion on this seam is the **stale** itself.
+- The stale reports `BadNoCommunication` while a DDEATH keeps `BadCommunicationError`: the death is the
+  source announcing its own offline state, the stale is our transport losing the broker (and matches
+  what the host's S15 fan-out writes). The existing const's "no driver emits BadNoCommunication at all"
+  remark was corrected rather than left to rot.

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

@@ -25,7 +25,7 @@
     {
       "id": "T4",
       "subject": "SparkplugIngestor: initial push on subscribe + connection-loss stale; rewrite the 'values are deliberately not staled' remark",
-      "status": "pending",
+      "status": "done",
       "blockedBy": [
         "T3"
       ]