feat: serverdata 资源目录 + serverrun 运维编排

- serverdata/：统一承载全部资源目录（data/logs/files/keys/prompts/uploads）
- data/→serverdata/data、templates/→serverdata/prompts、uploads/→serverdata/uploads
- config.py 集中 serverdata 路径；培训子应用 db/uploads 指到 serverdata
- serverrun/：start.sh（初始化资源目录+启动 dispatcher）、Dockerfile、docker-compose（core+compute-engine+redis+mysql）
- 66 测试全绿

serverdata/data/seed/demo_users.json

@@ -0,0 +1,13 @@
+[
+  {
+    "id": "u_demo_01",
+    "username": "pine",
+    "password": "123456",
+    "nickname": "云超服小助手",
+    "account": "云超服演示账号",
+    "company": "云超服科技",
+    "room": "1001",
+    "avatar": "",
+    "company_avatar": ""
+  }
+]