fix: Update database configuration for proper container naming

- Fix database name reference in docker-compose.yml
- Update config.go to use consistent database name
- Ensure database connection string matches container setup

internal/config/config.go

@@ -23,7 +23,7 @@ func LoadConfig() *Config {
 		DatabasePort:     getEnv("DATABASE_PORT", "5432"),
 		DatabaseUser:     getEnv("DATABASE_USER", "postgres"),
 		DatabasePassword: getEnv("DATABASE_PASSWORD", "password"),
-		DatabaseName:     getEnv("DATABASE_NAME", "ebookdb"),
+		DatabaseName:     getEnv("DATABASE_NAME", "bookmann"),
 		JWTSecret:        getEnv("JWT_SECRET", "your-secret-key"),
 		UploadPath:       getEnv("UPLOAD_PATH", "./uploads"),
 	}