Adv 2.0 D&D Phase R7: post-completion audit hardening

High-priority fixes from the multi-agent audit of Adventure 2.0:

- Phase 11 nil-deref cluster: zoneOrFallback() helper replaces 8 unsafe
  getZone(_) sites in dnd_zone_cmd.go. Corrupted zone IDs render a
  placeholder instead of panicking.
- Briefing/recap idempotency: deliverBriefing/deliverRecap now claim
  the rollover via a conditional UPDATE. Double-fires from clock skew
  or restart become no-ops; supply burn and day++ no longer reapply.
- Graceful ticker shutdown: AdventurePlugin gains stopCh + Stop(); all
  11 background tickers now select on stopCh in addition to ticker.C.
- Mood decay (§3.2): math.Round(elapsed*2) replaces int() truncation
  so sub-hour gaps decay correctly.
- 24h auto-abandon (§4.3): getActiveZoneRun returns clean slate and
  abandons stale runs whose LastActionAt is over 24h old.
- Respec / auto-migrate orphan cleanup: !respec and the auto-migrated
  draft wipe now abandon active zone runs and expeditions before
  deleting the dnd_character row.
- Phase R combat-link: applyBossDefeatThreat now wired from
  resolveBossRoom (-20 threat); applyRoomCombatThreatForUser adds
  +5/+8 from non-boss/elite kills (§8.1).
- Starvation → forced extraction: briefing-time check forces extract
  with §10.2 coin tax when supplies hit zero.
- GMNat20/Nat1 narration wired into resolveCombatRoom and
  resolveBossRoom (nat-20 takes precedence over nat-1).
- Treasure-undo race: LoadAndDelete on both timer-fire and `undo`
  paths so only one side wins.
- Battle Master: Disarming, Menacing, Parry maneuvers added (3 → 6
  of 10). Remaining 4 (Pushing, Goading, Riposte, Commander's Strike)
  documented inline as needing ally/reaction mechanics the engine
  doesn't model.
- Threat-70 warning: tracked in RegionState["siege_warning_fired"]
  so a drop-and-recross doesn't re-fire the beat.
- region_state JSON decode error now logged via slog.Warn instead
  of silently discarded.

Failing TestProdDB_DnDLayer fixed via option (a): track migrated
characters and only run round-trip / idempotency assertions on those,
skipping pre-existing prod-DB rows accumulated from live bot use.

New tests in dnd_audit_phase_R7_test.go cover: 24h auto-abandon,
briefing double-fire idempotency, threat-70 warning idempotency,
multi-region extract→resume state preservation, and starvation
forced-extraction.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/plugin/dnd_expedition_threat.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"gogobee/internal/flavor"
+	"maunium.net/go/mautrix/id"
 )
 
 // Phase 12 E2a — Threat Clock state machine.
@@ -134,9 +135,19 @@ func applyDailyThreatDrift(e *Expedition) (int, string, error) {
 	if newBand != prevBand && newBand > prevBand {
 		_ = appendThreatTransitionLog(e, newBand)
 	}
-	// E2c: §8.3 — one-time warning when crossing 70.
+	// E2c: §8.3 — one-time-per-expedition warning when crossing 70.
+	// Track in RegionState so a drop-and-recross (e.g. fortified-camp
+	// -5 followed by daily +3 drift) doesn't re-fire the beat.
 	if prevLevel < 70 && e.ThreatLevel >= 70 {
-		_ = appendApproachingSiegeLog(e)
+		warned, _ := e.RegionState["siege_warning_fired"].(bool)
+		if !warned {
+			_ = appendApproachingSiegeLog(e)
+			if e.RegionState == nil {
+				e.RegionState = map[string]any{}
+			}
+			e.RegionState["siege_warning_fired"] = true
+			_ = persistRegionState(e)
+		}
 	}
 	return delta, reason, nil
 }
@@ -246,3 +257,18 @@ func threatBandEffectsBlock(info ThreatBandInfo) string {
 func applyBossDefeatThreat(expID string) error {
 	return applyThreatDelta(expID, -20, "boss defeated")
 }
+
+// applyRoomCombatThreat records the +5 threat bump per §8.1 when the
+// player resolves combat in a new (non-boss) room. Silent no-op for
+// standalone zone runs (no active expedition).
+func applyRoomCombatThreatForUser(userID id.UserID, elite bool) {
+	exp, err := getActiveExpedition(userID)
+	if err != nil || exp == nil {
+		return
+	}
+	delta := 5
+	if elite {
+		delta = 8 // elite encounters are louder
+	}
+	_ = applyThreatDelta(exp.ID, delta, "combat in new room")
+}