fix(k8s): 同步 local 模式数据路径为 /app/sqlite3.db 与二进制同级

- deployment/quick-deploy: PVC 挂载 sqlite3.db/redka.db 到 /app/，含旧 data/ 迁移
- configmap 与 run.sh 状态输出对齐新路径
- README 补充 local 模式说明

backend/config/config.go

@@ -64,7 +64,7 @@ func Load() *Config {
 	viper.SetDefault("port", "8080")
 	viper.SetDefault("log_level", "info")
 	viper.SetDefault("database.driver", "sqlite")
-	viper.SetDefault("database.dbname", "data/aiops.db")
+	viper.SetDefault("database.dbname", "sqlite3.db")
 	viper.SetDefault("database.host", "localhost")
 	viper.SetDefault("database.port", 3306)
 	viper.SetDefault("database.charset", "utf8mb4")