feat: 系统优化 - ESLint、Tailwind、前端健壮性、后端工程化、运维可观测性

- 前端: ESLint+Prettier配置、Tailwind v4配置、ErrorBoundary、全局AuthLoader优化、ReactQuery分层
- 后端: MinIO凭证移除、Docker统一为govai品牌、zerolog日志封装、错误码枚举、文件上传校验、单元测试(13项全通过)
- 运维: 健康检查增强(PG/Redis ping)、Prometheus指标(/metrics端点)、多租户tenant包、RateLimit nil防御
- 移动: citation_prompt.txt → internal/assets/

server/internal/config/config.go

@@ -116,8 +116,8 @@ func Load() *Config {
 		},
 		MinIO: MinIOConfig{
 			Endpoint:  getEnv("MINIO_ENDPOINT", "localhost:9000"),
-			AccessKey: getEnv("MINIO_ACCESS_KEY", "minioadmin"),
-			SecretKey: getEnv("MINIO_SECRET_KEY", "minioadmin"),
+			AccessKey: getEnv("MINIO_ACCESS_KEY", ""),
+			SecretKey: getEnv("MINIO_SECRET_KEY", ""),
 			Bucket:    getEnv("MINIO_BUCKET", "aily-files"),
 			UseSSL:    false,
 		},