新增: df-miniapp uni-app跨端AI Chat(WS连relay透传+18变体AiChatEvent镜像)

- 脚手架: uni-app vue3 ts + 微信小程序manifest + pages(chat/conversations)+暗色主题
- WS客户端(ws.ts): uni.connectSocket连relay /ws/miniapp + Hello握手 + 指数退避重连 + 心跳Ping + JSON透传分派
- 类型镜像: events.ts AiChatEvent 18变体(对齐mod.rs grep核验) + relay.ts协议(BroadcastMessage/Hello/ControlMessage/MiniCommand)
- useAiChat: 18变体分派状态机(TextDelta累积/AgentRound flush/Tool状态/ConvState驱动generating) + send/stop/regenerate/switch + 乐观渲染
- 页面: chat(消息气泡/流式渲染/输入栏/工具调用展示) + conversations(列表占位)
- vue-tsc零错; 核验修正注释(变体数22→18, 心跳heartbeat→ping)
- 待对齐(Phase3联调): miniapp MiniCommand{cmd,args} vs df-tunnel TunnelCommand{kind,...} 格式需统一

df-miniapp/pages.json

@@ -0,0 +1,41 @@
+{
+  "pages": [
+    {
+      "path": "pages/chat/index",
+      "style": {
+        "navigationBarTitleText": "AI 对话",
+        "enablePullDownRefresh": false
+      }
+    },
+    {
+      "path": "pages/conversations/index",
+      "style": {
+        "navigationBarTitleText": "会话列表",
+        "enablePullDownRefresh": true
+      }
+    }
+  ],
+  "globalStyle": {
+    "navigationBarTextStyle": "white",
+    "navigationBarTitleText": "DevFlow",
+    "navigationBarBackgroundColor": "#1a1a1a",
+    "backgroundColor": "#0f0f0f",
+    "backgroundTextStyle": "light"
+  },
+  "tabBar": {
+    "color": "#999999",
+    "selectedColor": "#4a9eff",
+    "backgroundColor": "#1a1a1a",
+    "borderStyle": "black",
+    "list": [
+      {
+        "pagePath": "pages/chat/index",
+        "text": "对话"
+      },
+      {
+        "pagePath": "pages/conversations/index",
+        "text": "会话"
+      }
+    ]
+  }
+}