feat: 重构项目心跳数据结构并实现项目列表API

- 新增统一项目列表Redis键和迁移工具
- 实现GET /api/projects端点获取项目列表
- 实现POST /api/projects/migrate端点支持数据迁移
- 更新前端ProjectSelector组件使用真实项目数据
- 扩展projectStore状态管理
- 更新相关文档和OpenSpec规范
- 添加测试用例验证新功能

src/backend/routes/projects.integration.test.js

@@ -0,0 +1,62 @@
+import { describe, expect, it } from 'vitest';
+import request from 'supertest';
+
+import { createApp } from '../app.js';
+import { createFakeRedis } from '../test/fakeRedis.js';
+
+describe('projects API', () => {
+  it('GET /api/projects returns projects from unified list', async () => {
+    const now = Date.now();
+    const redis = createFakeRedis({
+      项目心跳: JSON.stringify([
+        { projectName: 'Demo', apiBaseUrl: 'http://localhost:8080', lastActiveAt: now },
+      ]),
+    });
+
+    const app = createApp({ redis });
+    const resp = await request(app).get('/api/projects');
+
+    expect(resp.status).toBe(200);
+    expect(resp.body.success).toBe(true);
+    expect(resp.body.count).toBe(1);
+    expect(resp.body.projects[0]).toMatchObject({
+      id: 'Demo',
+      name: 'Demo',
+      apiBaseUrl: 'http://localhost:8080',
+    });
+    expect([ 'online', 'offline', 'unknown' ]).toContain(
+      resp.body.projects[0].status,
+    );
+  });
+
+  it('POST /api/projects/migrate migrates old *_项目心跳 keys into 项目心跳 list', async () => {
+    const now = Date.now();
+    const redis = createFakeRedis({
+      'A_项目心跳': JSON.stringify({
+        apiBaseUrl: 'http://a',
+        lastActiveAt: now,
+      }),
+    });
+
+    const app = createApp({ redis });
+    const resp = await request(app)
+      .post('/api/projects/migrate')
+      .send({ dryRun: false, deleteOldKeys: true });
+
+    expect(resp.status).toBe(200);
+    expect(resp.body.success).toBe(true);
+    expect(resp.body.migrated).toBe(1);
+
+    const listRaw = await redis.get('项目心跳');
+    expect(typeof listRaw).toBe('string');
+    const list = JSON.parse(listRaw);
+    expect(Array.isArray(list)).toBe(true);
+    expect(list[0]).toMatchObject({
+      projectName: 'A',
+      apiBaseUrl: 'http://a',
+    });
+
+    const old = await redis.get('A_项目心跳');
+    expect(old).toBeNull();
+  });
+});