fix(agent): 输入草稿按会话保留,切换会话、关抽屉不丢

会话面板与新对话输入框的草稿原来是组件内状态,切到别的会话或 Esc 关抽屉就没了。
改为按会话(以及列表页 / 抽屉两处新对话)分键记在模块里,发送成功后清掉。

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Cxwgnn2pbzQ7rXv3rq7fei

apps/web/app/components/agent/agent-run-panel.tsx

@@ -40,6 +40,7 @@ import {
   runPlanIds,
 } from "./agent-conversation.tsx";
 import { RunPlan } from "./agent-interaction.tsx";
+import { readDraft, runDraftKey, writeDraft } from "./agent-nav.ts";
 import { shortGoalTitle } from "./agent-store.ts";
 import { SubagentTree } from "./agent-subagent-tree.tsx";
 import { callCounts, sessionStatsParts, stepProgress } from "./conversation-model.ts";
@@ -71,6 +72,7 @@ export function GoalComposer({
   onClearContext,
   defaultGoal = "",
   suggestions,
+  draftKey,
 }: {
   onSubmit: (goal: string, opts: AgentSessionOptions) => void;
   pending: boolean;
@@ -80,8 +82,14 @@ export function GoalComposer({
   defaultGoal?: string;
   /** 快捷目标:输入框为空时显示 */
   suggestions?: string[];
+  /** 草稿记在这个键下(没有预填目标时恢复);发送成功后由调用方清掉 */
+  draftKey?: string;
 }) {
-  const [goal, setGoal] = useState(defaultGoal);
+  const [goal, setGoalState] = useState(() => defaultGoal || readDraft(draftKey));
+  const setGoal = (text: string) => {
+    setGoalState(text);
+    writeDraft(draftKey, text);
+  };
   const box = useRef<HTMLDivElement>(null);
   const fill = (text: string) => {
     setGoal(text);
@@ -295,7 +303,12 @@ export function AgentRunPanel({
   const append = useAppendAgentMessage();
   const create = useCreateAgentRun();
   const navigate = useNavigate();
-  const [msg, setMsg] = useState("");
+  // 草稿按会话记:切到别的会话再回来还在,不会串到别的会话
+  const [msg, setMsgState] = useState(() => readDraft(runDraftKey(runId)));
+  const setMsg = (text: string) => {
+    setMsgState(text);
+    writeDraft(runDraftKey(runId), text);
+  };
   const [confirmStop, setConfirmStop] = useState(false);
   const sseStatus = useSseStatus();
   const qc = useQueryClient();