Fix deployment issues and add threads, numbered watchlist, search URL encoding

- Fix SQLite connection string (drop query param, use explicit PRAGMA)
- Register sqlite3-fk-wal driver for mautrix cryptohelper (pure Go, no CGO)
- Fetch DeviceID via /whoami when using bare access token
- Log cross-signing results at Warn/Info instead of Debug
- Post deals into Matrix threads: Game Deals, DLC Deals, Epic Free Games
- Add numbered watchlist; !extend and !unwatch accept list numbers
- URL-encode search queries for multi-word !search commands
- Add GetConfig/SetConfig helpers for persistent thread event IDs

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

internal/database/database.go

@@ -12,13 +12,16 @@ type DB struct {
 }
 
 func Open(path string) (*DB, error) {
-	db, err := sqlx.Open("sqlite", path+"?_pragma=journal_mode(WAL)")
+	db, err := sqlx.Open("sqlite", path)
 	if err != nil {
 		return nil, err
 	}
 	if err := db.Ping(); err != nil {
 		return nil, err
 	}
+	if _, err := db.Exec("PRAGMA journal_mode=WAL"); err != nil {
+		return nil, err
+	}
 	d := &DB{db: db}
 	if err := d.migrate(); err != nil {
 		return nil, err
@@ -97,6 +100,22 @@ func (d *DB) SetFirstRunDone() error {
 	return err
 }
 
+// GetConfig retrieves a value from the config table.
+func (d *DB) GetConfig(key string) (string, error) {
+	var val string
+	err := d.db.Get(&val, "SELECT value FROM config WHERE key = ?", key)
+	return val, err
+}
+
+// SetConfig sets a value in the config table.
+func (d *DB) SetConfig(key, value string) error {
+	_, err := d.db.Exec(
+		"INSERT OR REPLACE INTO config (key, value) VALUES (?, ?)",
+		key, value,
+	)
+	return err
+}
+
 // PruneOldDeals removes deals older than the given number of days.
 func (d *DB) PruneOldDeals(days int) error {
 	cutoff := time.Now().AddDate(0, 0, -days).UTC().Format(time.RFC3339)