logtail: the sweep closes only queued rows, with reason "reconcile" (audit H3)

reconcile() closed a row through UpdateStatus (WHERE queue_id AND to_addr),
which could overwrite a "sent" the tailer wrote between the listing and the
close, and rewrite an old row of a reused queue id. store.CloseUnreported
sets status bounced and reason "reconcile" (store.ReasonReconcile; the
0006 column, no schema change) WHERE ... AND status = 'queued'; the sweep
counts rows actually closed.

Tests: store - a queued row is closed with the reason, a sent row is left
alone (0 rows); logtail - the sweep's close goes through CloseUnreported.

CHANGELOG [Unreleased], audit plan line ticked, roadmap 9/61.
Evidence: go vet ./... clean; go test ./internal/store ok, ./internal/logtail
ok but for TestFollowTailsAndRotates (Windows rename of an open file, fails
here always); the server run of the stage follows before the push.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/audit-2026-10-12.md

@@ -596,7 +596,7 @@ has already run is never edited — the next file is added; the published
 - [x] **`QueueIDs` on a truncated listing returns an error**, as `postqueueJSON`
    does; `reconcile` already treats an error as no information. Test: a 5 MiB
    fake `postqueue -p`. — **Opus**
-- [ ] **Reconcile only closes `queued` rows** (`AND status = 'queued'` in the
+- [x] **Reconcile only closes `queued` rows** (`AND status = 'queued'` in the
    reconcile path's update) and marks what it closed: `reason = 'reconcile'`
    on the row (the 0006 column; a new value, no schema change). — **Opus**
 - [ ] **Measure before deciding the sweep's fate** (owner, 2026-10-12: the