Show error when remote branch status is unavailable (Vibe Kanban) (#1825)

* I've completed the implementation. Here's a summary of the changes:

## Summary

### Changes Made

1. **`frontend/src/hooks/useBranchStatus.ts`**
   - Modified to return `{ data, error, isError, isLoading, refetch }` instead of just the query result
   - This exposes the error state to consuming components

2. **`frontend/src/components/tasks/Toolbar/GitOperations.tsx`**
   - Added `branchStatusError` prop to interface
   - Removed `hasConflictsCalculated` from the "Change target branch" button's disabled condition - now it stays enabled even during errors, allowing users to recover
   - Changed the actions section from hiding completely when `selectedRepoStatus` is null to showing an error message when there's a `branchStatusError`

3. **`frontend/src/components/dialogs/tasks/GitActionsDialog.tsx`**
   - Extracted `error` from `useBranchStatus` and passes it to `GitOperations` as `branchStatusError`

4. **`frontend/src/pages/ProjectTasks.tsx`**
   - Updated `DiffsPanelContainer` to accept and pass `branchStatusError`
   - Extracted `branchStatusError` from `useBranchStatus` hook
   - Passes the error through to `DiffsPanelContainer`

5. **i18n translation files** (all 6 locales: en, es, ja, ko, zh-Hans, zh-Hant)
   - Added `git.errors.branchStatusUnavailable` translation string

### Behavior Changes

- **Before**: When branch status API failed, git operations (Merge, PR/Push, Rebase buttons) were completely hidden
- **After**:
  - An error message is shown: "Unable to fetch branch status. You can still change the target branch."
  - The "Change target branch" button remains enabled, allowing users to recover from deadlock situations
  - Users can see something went wrong instead of the UI silently failing

* Cleanup script changes for workspace cdcbb9c6-fc9f-45bf-9c30-0e432d06cccf

* Simplify useBranchStatus hook return

Return useQuery result directly instead of manually constructing an object.
The useQuery hook already returns all needed properties (data, error, isError, isLoading, refetch).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Restore hasConflictsCalculated check for change target branch button

The conflict check wasn't needed for the branch status error fix.
Keeping it prevents changing target branch during active git conflicts.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/components/dialogs/tasks/GitActionsDialog.tsx

@@ -35,7 +35,9 @@ function GitActionsDialogContent({
   task,
 }: GitActionsDialogContentProps) {
   const { t } = useTranslation('tasks');
-  const { data: branchStatus } = useBranchStatus(attempt.id);
+  const { data: branchStatus, error: branchStatusError } = useBranchStatus(
+    attempt.id
+  );
   const { isAttemptRunning } = useAttemptExecution(attempt.id);
   const { error: gitError } = useGitOperationsError();
   const { repos, selectedRepoId } = useAttemptRepo(attempt.id);
@@ -83,6 +85,7 @@ function GitActionsDialogContent({
         selectedAttempt={attempt}
         task={task}
         branchStatus={branchStatus ?? null}
+        branchStatusError={branchStatusError}
         isAttemptRunning={isAttemptRunning}
         selectedBranch={getSelectedRepoStatus()?.target_branch_name ?? null}
         layout="vertical"

frontend/src/components/tasks/Toolbar/GitOperations.tsx

@@ -35,6 +35,7 @@ interface GitOperationsProps {
   selectedAttempt: Workspace;
   task: TaskWithAttemptStatus;
   branchStatus: RepoBranchStatus[] | null;
+  branchStatusError?: Error | null;
   isAttemptRunning: boolean;
   selectedBranch: string | null;
   layout?: 'horizontal' | 'vertical';
@@ -46,6 +47,7 @@ function GitOperations({
   selectedAttempt,
   task,
   branchStatus,
+  branchStatusError,
   isAttemptRunning,
   selectedBranch,
   layout = 'horizontal',
@@ -463,7 +465,12 @@ function GitOperations({
         )}
 
         {/* Right: Actions */}
-        {selectedRepoStatus && (
+        {branchStatusError && !selectedRepoStatus ? (
+          <div className="flex items-center gap-2 text-xs text-destructive">
+            <AlertTriangle className="h-3.5 w-3.5" />
+            <span>{t('git.errors.branchStatusUnavailable')}</span>
+          </div>
+        ) : selectedRepoStatus ? (
           <div className={actionsClasses}>
             <Button
               onClick={handleMergeClick}
@@ -523,7 +530,7 @@ function GitOperations({
               <span className="truncate max-w-[10ch]">{rebaseButtonLabel}</span>
             </Button>
           </div>
-        )}
+        ) : null}
       </div>
     </div>
   );

frontend/src/i18n/locales/en/tasks.json

@@ -257,7 +257,8 @@
       "changeTargetBranch": "Failed to change target branch",
       "pushChanges": "Failed to push changes",
       "mergeChanges": "Failed to merge changes",
-      "rebaseBranch": "Failed to rebase branch"
+      "rebaseBranch": "Failed to rebase branch",
+      "branchStatusUnavailable": "Unable to fetch branch status. You can still change the target branch."
     },
     "pr": {
       "open": "Open PR #{{number}}",

frontend/src/i18n/locales/es/tasks.json

@@ -235,7 +235,8 @@
       "changeTargetBranch": "Error al cambiar rama de destino",
       "mergeChanges": "Error al fusionar cambios",
       "pushChanges": "Error al enviar cambios",
-      "rebaseBranch": "Error al hacer rebase de la rama"
+      "rebaseBranch": "Error al hacer rebase de la rama",
+      "branchStatusUnavailable": "No se puede obtener el estado de la rama. Aún puedes cambiar la rama de destino."
     },
     "labels": {
       "taskBranch": "Rama de tarea"

frontend/src/i18n/locales/ja/tasks.json

@@ -235,7 +235,8 @@
       "changeTargetBranch": "ターゲットブランチの変更に失敗しました",
       "mergeChanges": "変更のマージに失敗しました",
       "pushChanges": "変更のプッシュに失敗しました",
-      "rebaseBranch": "ブランチのリベースに失敗しました"
+      "rebaseBranch": "ブランチのリベースに失敗しました",
+      "branchStatusUnavailable": "ブランチのステータスを取得できません。ターゲットブランチの変更は引き続き可能です。"
     },
     "labels": {
       "taskBranch": "タスクブランチ"

frontend/src/i18n/locales/ko/tasks.json

@@ -235,7 +235,8 @@
       "changeTargetBranch": "대상 브랜치를 변경하지 못했습니다",
       "mergeChanges": "변경사항을 병합하지 못했습니다",
       "pushChanges": "변경사항을 푸시하지 못했습니다",
-      "rebaseBranch": "브랜치를 리베이스하지 못했습니다"
+      "rebaseBranch": "브랜치를 리베이스하지 못했습니다",
+      "branchStatusUnavailable": "브랜치 상태를 가져올 수 없습니다. 대상 브랜치는 여전히 변경할 수 있습니다."
     },
     "labels": {
       "taskBranch": "작업 브랜치"

frontend/src/i18n/locales/zh-Hans/tasks.json

@@ -270,7 +270,8 @@
       "changeTargetBranch": "更改目标分支失败",
       "pushChanges": "推送更改失败",
       "mergeChanges": "合并更改失败",
-      "rebaseBranch": "变基分支失败"
+      "rebaseBranch": "变基分支失败",
+      "branchStatusUnavailable": "无法获取分支状态。您仍然可以更改目标分支。"
     },
     "pr": {
       "open": "打开 PR #{{number}}",

frontend/src/i18n/locales/zh-Hant/tasks.json

@@ -270,7 +270,8 @@
       "changeTargetBranch": "變更目標分支失敗",
       "pushChanges": "推送變更失敗",
       "mergeChanges": "合併變更失敗",
-      "rebaseBranch": "重基底分支失敗"
+      "rebaseBranch": "重基底分支失敗",
+      "branchStatusUnavailable": "無法取得分支狀態。您仍然可以變更目標分支。"
     },
     "pr": {
       "open": "開啟 PR #{{number}}",

frontend/src/pages/ProjectTasks.tsx

@@ -102,10 +102,12 @@ function DiffsPanelContainer({
   attempt,
   selectedTask,
   branchStatus,
+  branchStatusError,
 }: {
   attempt: Workspace | null;
   selectedTask: TaskWithAttemptStatus | null;
   branchStatus: RepoBranchStatus[] | null;
+  branchStatusError?: Error | null;
 }) {
   const { isAttemptRunning } = useAttemptExecution(attempt?.id);
 
@@ -118,6 +120,7 @@ function DiffsPanelContainer({
           ? {
               task: selectedTask,
               branchStatus: branchStatus ?? null,
+              branchStatusError,
               isAttemptRunning,
               selectedBranch: branchStatus?.[0]?.target_branch_name ?? null,
             }
@@ -284,7 +287,9 @@ export function ProjectTasks() {
   const isTaskView = !!taskId && !effectiveAttemptId;
   const { data: attempt } = useTaskAttemptWithSession(effectiveAttemptId);
 
-  const { data: branchStatus } = useBranchStatus(attempt?.id);
+  const { data: branchStatus, error: branchStatusError } = useBranchStatus(
+    attempt?.id
+  );
 
   const rawMode = searchParams.get('view') as LayoutMode;
   const mode: LayoutMode =
@@ -1000,6 +1005,7 @@ export function ProjectTasks() {
             attempt={attempt}
             selectedTask={selectedTask}
             branchStatus={branchStatus ?? null}
+            branchStatusError={branchStatusError}
           />
         )}
       </div>