refactor(frontend): 拆 types.ts(871) / ws.ts::dispatchFrame(266)（纯搬移 + barrel）

执行方案 DevDocs/audit/_plan.md 阶段 0 · G0-D：
- lib/types.ts(871) → lib/types/ 11 个域文件 + 14 行 `export *` barrel（仿 lib/api.ts 先例）
  chat / ws / session / agent / flow / persona / api / admin(269) / adminWrite(176) / kook /
  notification
- lib/ws.ts(494) → 203 行入口 + lib/ws/handlers/ 8 文件；dispatchFrame(266 行) 改为按组
  分发链（7 个 handler 各持一组 case，命中 return true，未命中走原 default 兜底），
  33 个 case 标签一一守恒

机械证明：type 导出集 86 个守恒（拆后并集 diff 为空）；去掉空行与 import/export 语句后
**784=784 行、排序 diff 为空**；dispatchFrame 的 case 标签集 33=33 守恒；ws.ts 的
scheduleReconnect 至文件尾与 HEAD 字节级一致。
65 个 lib/types 消费方 + 3 个 lib/ws 消费方**零改动**通过 —— tsc 0 错误正是这一点的强判据。

验证：npx tsc --noEmit 0 错误；npm run build 成功；9 个前端逻辑测试全绿（含真实驱动
拆后 dispatchFrame 的 messageSync 54 checks 与 personaSession 23 checks）；
最大文件 admin.ts 269 行、最大函数 openSocket 72 行（均达标）。

frontend/web/src/lib/ws/handlers/stream.ts

@@ -0,0 +1,47 @@
+import { streamFrameApplies } from "../../streamScope";
+import type { FrameEvent, FramePayload, StoreState } from "./shared";
+
+/** 流式正文帧处理组：stream_chunk / stream_end / message.start / message.delta /
+ *  message.end。命中（含组内主动丢弃）返回 true，未命中返回 false 交给下一组。 */
+export function handleStreamEvent(ev: FrameEvent, r: FramePayload, s: StoreState): boolean {
+  switch (ev.type) {
+    case "stream_chunk": {
+      if (!streamFrameApplies(ev, r, s.activeSessionId)) return true;
+      if (r && typeof r.delta === "string") s.appendChunk(r.delta);
+      return true;
+    }
+    case "stream_end": {
+      // Another session's turn ending must not close the streaming bubble on
+      // screen or clear this conversation's busy badge (both are single-slot
+      // state: the last message's flag, and one shell-wide `sessionBusy`).
+      if (!streamFrameApplies(ev, r, s.activeSessionId)) return true;
+      s.endStream();
+      // The assistant reply stopped streaming, so the immediate turn is over:
+      // close the busy/pending window so the badge does not stick. If the backend
+      // keeps a task/subagent running it re-emits session_busy (design/15 §5).
+      s.setSessionBusy(false, 0);
+      if (r && typeof r.stopReason === "string") {
+        s.setContext({ lastAgentMode: s.context.lastAgentMode });
+      }
+      return true;
+    }
+    // Structured stream events (design/04 §1.1, aligned with OpenClaw). These
+    // arrive in place of the legacy stream_chunk when the loop streams events.
+    case "message.start": {
+      // The assistant bubble is already opened by useChat; nothing to do here.
+      return true;
+    }
+    case "message.delta": {
+      if (!streamFrameApplies(ev, r, s.activeSessionId)) return true;
+      if (r && typeof r.delta === "string") s.appendChunk(r.delta);
+      return true;
+    }
+    case "message.end": {
+      // Body-text segment closed; the turn may continue with tool calls, so we
+      // do NOT end the stream here (stream_end owns that).
+      return true;
+    }
+    default:
+      return false;
+  }
+}