fix(web): renderPreview 中 task 变量遮蔽全局 t() 翻译函数导致预览点击无效

将 renderPreview 内 const t = tasks.find() 改名为 task，
避免局部变量 t（任务对象）遮蔽全局翻译函数 t()，
使预览面板渲染时抛 't is not a function' 导致面板无法打开。

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/app.js

@@ -1191,14 +1191,14 @@ function renderTranscript(messages) {
 function renderPreview() {
   const root = $('#previewRoot');
   if (!S.previewId) { root.hidden = true; root.innerHTML = ''; return; }
-  const t = S.approvals.find((x) => x.id === S.previewId) || S.tasks.find((x) => x.id === S.previewId);
+  const task = S.approvals.find((x) => x.id === S.previewId) || S.tasks.find((x) => x.id === S.previewId);
   // 任务已离开闸（被裁决/状态变化）→ 自动关闭
-  if (!t || !GATE_OF[t.status]) { S.previewId = null; S.previewReject = false; root.hidden = true; root.innerHTML = ''; return; }
+  if (!task || !GATE_OF[task.status]) { S.previewId = null; S.previewReject = false; root.hidden = true; root.innerHTML = ''; return; }
-  const gate = GATE_OF[t.status];
+  const gate = GATE_OF[task.status];
   const pp = S.projects.find((x) => x.id === S.currentProjectId);
   const defBranch = pp ? pp.defaultBranch : 'main';
   const onlyPassBtn = gate === 'exec'
-    ? `<button class="btn btn-ghost btn-xs" data-action="gate-accept" data-merge="false" data-id="${esc(t.id)}" title="${t('gateOnlyPass')}">${t('gateOnlyPass')}</button>`
+    ? `<button class="btn btn-ghost btn-xs" data-action="gate-accept" data-merge="false" data-id="${esc(task.id)}" title="${t('gateOnlyPass')}">${t('gateOnlyPass')}</button>`
     : '';
   root.hidden = false;
   root.innerHTML = `
@@ -1206,28 +1206,28 @@ function renderPreview() {
     <div class="preview-panel">
       <div class="preview-head">
         <span class="gate-kind">${gateLabel(gate)}</span>
-        <span class="preview-title">${esc(t.title)}</span>
+        <span class="preview-title">${esc(task.title)}</span>
-        ${cplxBadge(t.complexity)}
+        ${cplxBadge(task.complexity)}
-        ${statusChip(t.status)}
+        ${statusChip(task.status)}
         <span class="spacer"></span>
         <button class="btn btn-ghost" data-action="preview-close" title="${t('closeTip')}">${icon('close')}</button>
       </div>
-      <div class="preview-body">${gateDocs(t)}</div>
+      <div class="preview-body">${gateDocs(task)}</div>
       <div class="preview-foot">
-        <button class="btn btn-accept" data-action="gate-accept" data-id="${esc(t.id)}">${gate === 'exec' ? t('gateAcceptMerge') : t('gateAccept')}</button>${onlyPassBtn}
+        <button class="btn btn-accept" data-action="gate-accept" data-id="${esc(task.id)}">${gate === 'exec' ? t('gateAcceptMerge') : t('gateAccept')}</button>${onlyPassBtn}
-        <button class="btn btn-reject" data-action="preview-reject-toggle" data-id="${esc(t.id)}">${t('gateReject')}</button>
+        <button class="btn btn-reject" data-action="preview-reject-toggle" data-id="${esc(task.id)}">${t('gateReject')}</button>
         ${gate === 'exec' ? `<span class="proj-meta">${t('gateMergeNote', { branch: esc(defBranch) })}</span>` : ''}
-        <span class="proj-meta">id ${esc(t.id)} · ${fmtTime(t.updatedAt)}</span>
+        <span class="proj-meta">id ${esc(task.id)} · ${fmtTime(task.updatedAt)}</span>
         ${S.previewReject ? `
         <div class="reject-form preview-reject">
-          <textarea id="prev-rej-${esc(t.id)}" placeholder="${t('rejectPlaceholder')}"></textarea>
+          <textarea id="prev-rej-${esc(task.id)}" placeholder="${t('rejectPlaceholder')}"></textarea>
-          <button class="btn btn-reject" data-action="gate-reject-confirm" data-id="${esc(t.id)}" data-ta="prev-rej-${esc(t.id)}">${t('confirmReject')}</button>
+          <button class="btn btn-reject" data-action="gate-reject-confirm" data-id="${esc(task.id)}" data-ta="prev-rej-${esc(task.id)}">${t('confirmReject')}</button>
-          <button class="btn" data-action="preview-reject-toggle" data-id="${esc(t.id)}">${t('collapse')}</button>
+          <button class="btn" data-action="preview-reject-toggle" data-id="${esc(task.id)}">${t('collapse')}</button>
         </div>` : ''}
       </div>
     </div>`;
   if (S.previewReject) {
-    const ta = document.getElementById(`prev-rej-${t.id}`);
+    const ta = document.getElementById(`prev-rej-${task.id}`);
     if (ta) ta.focus();
   }
 }