Add housing/pets/Thom Krooke, wordle overhaul, boost system, backup strategy

Part 3 (Housing, Thom Krooke & Pets):
- Housing system with tiered upgrades, mortgage loans, FRED API rates
- Thom Krooke realtor NPC with !thom commands and !thom pay extra principal
- Pet system with arrival, naming, leveling, combat, morning defense
- Pet ditch recovery scales with level, name validation

Wordle overhaul:
- Remove daily expiration — puzzles persist until solved/failed
- Auto-start new puzzle after solve, fail, or skip
- Sequential puzzle IDs instead of date-based
- Auto-create puzzle on first guess if none active

Adventure fixes:
- Double XP/money boost toggle (!adv boost, admin only)
- Fix ensureCharacter wiping existing data on query errors
- Fix rival RPS format string bug
- Fix daily summary empty data (load today+yesterday logs)
- Fix holdem DM-to-room reply routing
- Fix Robbie payout to 25% of item value
- Add fishing to leaderboard and TwinBee calculations
- Add Thom to morning menu
- Persist mortgage rate across restarts via db.CacheGet/Set

Infrastructure:
- Daily database backup via VACUUM INTO with 7-day retention
- Admin DM notification on backup failure (async)
- Daily NPC house balance reset for holdem

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/plugin/holdem.go

@@ -97,12 +97,14 @@ func (p *HoldemPlugin) OnMessage(ctx MessageContext) error {
 	}
 
 	// If this is a DM, resolve the player's game room so actions route correctly.
+	// Clear EventID so replies go as plain messages — the room can't resolve DM events.
 	if isDM {
 		p.mu.Lock()
 		gameRoom := p.findGameRoom(ctx.Sender)
 		p.mu.Unlock()
 		if gameRoom != "" {
 			ctx.RoomID = gameRoom
+			ctx.EventID = ""
 		}
 	}
 
@@ -1216,6 +1218,14 @@ func (p *HoldemPlugin) updateNPCBalance(delta int64) {
 		delta, p.cfg.NPCName)
 }
 
+// resetNPCHouseBalance resets all NPC balances to the configured house balance.
+// Called daily at midnight.
+func resetNPCHouseBalance() {
+	balance := int64(envInt("HOLDEM_NPC_HOUSE_BALANCE", 10000))
+	db.Exec("holdem: reset npc balance",
+		`UPDATE holdem_npc_balance SET balance = ?`, balance)
+}
+
 func (p *HoldemPlugin) recordScores(game *HoldemGame, winnings map[id.UserID]int64) {
 	for _, pl := range game.Players {
 		if pl.IsNPC {