Adv 2.0 D&D polish: GM→DM rename, streamed zone combat, end-to-end scenario test

GM→DM rename across docs and code (GMNarrationType→DMNarrationType,
GMState→DMState, narration constants, comments) so the system reads as
"Dungeon Master" everywhere. Player-visible "GM mood" wording stays
where it appears in flavor.

Streamed zone/expedition combat: zone advance now stages patrol →
patrol play-by-play → patrol resolution → room intro → room play-by-play
→ final outcome through sendZoneCombatMessages with 2–3s pacing
(arena keeps its 5–8s window). Combat narrative lines pick up a compact
d20-vs-AC roll annotation for hit/crit/miss/block events.

Combat outcome polish: dndHPSnapshot lets narration show sheet HP
rather than legacy combat-engine HP, and markAdventureDead clears the
zombie state where hp_current was 0 but the legacy alive flag stayed
true after a D&D-layer KO.

Adv 2.0 announcement (ADVENTURE_2.0_ANNOUNCEMENT.md), README rewrite
covering the new layer, and adv2_scenario_test.go — a full
zone-run + expedition + harvest playthrough against a copy of the prod
DB asserting persisted state end-to-end.

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

internal/plugin/combat_bridge.go

@@ -328,12 +328,27 @@ func (p *AdventurePlugin) prependCraftNarrative(userID id.UserID, messages []str
 // Runs in a goroutine so it doesn't block the message handler.
 // Returns a channel that is closed when all messages have been sent.
 func (p *AdventurePlugin) sendCombatMessages(userID id.UserID, phaseMessages []string, finalMessage string) <-chan struct{} {
+	return p.sendCombatMessagesWithDelay(userID, phaseMessages, finalMessage, 5, 4) // 5–8s
+}
+
+// sendZoneCombatMessages is the zone/expedition variant — same staging as
+// arena, but tighter pacing (2–3s) so dungeon advances feel snappier.
+func (p *AdventurePlugin) sendZoneCombatMessages(userID id.UserID, phaseMessages []string, finalMessage string) <-chan struct{} {
+	return p.sendCombatMessagesWithDelay(userID, phaseMessages, finalMessage, 2, 2) // 2–3s
+}
+
+// sendCombatMessagesWithDelay is the shared streamer. base/jitter define
+// the per-message delay window in seconds: delay = base + rand.IntN(jitter).
+func (p *AdventurePlugin) sendCombatMessagesWithDelay(userID id.UserID, phaseMessages []string, finalMessage string, base, jitter int) <-chan struct{} {
 	done := make(chan struct{})
 	go func() {
 		defer close(done)
 		for _, msg := range phaseMessages {
 			_ = p.SendDM(userID, msg)
-			delay := 5 + rand.IntN(4) // 5-8 seconds
+			delay := base
+			if jitter > 0 {
+				delay += rand.IntN(jitter)
+			}
 			time.Sleep(time.Duration(delay) * time.Second)
 		}
 		_ = p.SendDM(userID, finalMessage)