refactor(repo): consolidate openflare-server to root and move subprojects to internal/apps

- Merge all files inside openflare-server to the repository root directory.
- Relocate agent, relay, and flared subprojects from internal/ to internal/apps/.
- Combine docker-compose files and update build context paths to root.
- Update GitHub workflows and Dockerfiles to refer to new directories and package names.
- Rewrite Go package imports across all files.
- Resolve database renew test race condition and clean up docs.

frontend/lib/services/config/config.service.ts

@@ -0,0 +1,23 @@
+import {BaseService} from '@/lib/services/core';
+import type {PublicConfigResponse} from './types';
+
+/**
+ * 配置服务
+ * 处理系统公共配置相关的 API 请求
+ */
+export class ConfigService extends BaseService {
+  protected static readonly basePath = '/api/v1/config';
+
+  /**
+   * 获取公共配置
+   * @returns 公共配置信息
+   *
+   * @example
+   * ```typescript
+   * const config = await ConfigService.getPublicConfig();
+   * ```
+   */
+  static async getPublicConfig(): Promise<PublicConfigResponse> {
+    return this.get<PublicConfigResponse>('/public');
+  }
+}