refactor(database): move database initialization functions to single file

Consolidate InitFrpcDatabase and InitUserDatabase functions into database.go for better code organization and maintainability. Remove duplicate code from frpc.go.

frpc.go

@@ -49,40 +49,6 @@ type FrpcInstance struct {
 
 var frpcDB *sql.DB
 
-func InitFrpcDatabase(dbPath string) error {
-	var err error
-	frpcDB, err = sql.Open("sqlite", dbPath)
-	if err != nil {
-		return fmt.Errorf("failed to open frpc database: %w", err)
-	}
-
-	if err = frpcDB.Ping(); err != nil {
-		return fmt.Errorf("failed to ping frpc database: %w", err)
-	}
-
-	createTableSQL := `
-	CREATE TABLE IF NOT EXISTS frpcInstances (
-		id INTEGER PRIMARY KEY AUTOINCREMENT,
-		userID INTEGER NOT NULL,
-		name TEXT NOT NULL,
-		serverAddr TEXT NOT NULL,
-		serverPort TEXT NOT NULL,
-		auth_method TEXT NOT NULL,
-		bootAtStart INTEGER NOT NULL DEFAULT 0,
-		runUser TEXT NOT NULL DEFAULT 'root',
-		configPath TEXT NOT NULL,
-		createdAt TEXT NOT NULL,
-		UNIQUE(userID, name)
-	);
-	`
-	_, err = frpcDB.Exec(createTableSQL)
-	if err != nil {
-		return fmt.Errorf("failed to create frpcInstances table: %w", err)
-	}
-
-	return nil
-}
-
 func CloseFrpcDatabase() error {
 	if frpcDB != nil {
 		return frpcDB.Close()