fix(FN-2555): restore execution mode updates from task edit flow

- Add explicit executionMode props to TaskForm edit controls and render a Standard/Fast selector in More Options
- Track editExecutionMode state in TaskDetailModal and reset it consistently when opening, canceling, or syncing task changes
- Include executionMode in update payload diffing so standard→fast sends "fast" and fast→standard clears to null
- Add regression tests for TaskForm selector behavior and TaskDetailModal update payload handling

packages/dashboard/app/components/TaskDetailModal.tsx

@@ -227,6 +227,10 @@ function normalizeTaskPriorityValue(priority: Task["priority"]): TaskPriority {
     : DEFAULT_TASK_PRIORITY;
 }
 
+function normalizeExecutionModeValue(executionMode: Task["executionMode"]): "standard" | "fast" {
+  return executionMode === "fast" ? "fast" : "standard";
+}
+
 const DESCRIPTION_TRUNCATE_LENGTH = 200;
 
 const EDITABLE_COLUMNS: Set<Column> = new Set(["triage", "todo"]);
@@ -342,6 +346,7 @@ export function TaskDetailModal({
   const [editPresetMode, setEditPresetMode] = useState<"default" | "preset" | "custom">("default");
   const [editReviewLevel, setEditReviewLevel] = useState<number | undefined>(undefined);
   const [editPriority, setEditPriority] = useState<TaskPriority>(DEFAULT_TASK_PRIORITY);
+  const [editExecutionMode, setEditExecutionMode] = useState<"standard" | "fast">(normalizeExecutionModeValue(task.executionMode));
   const [editSelectedPresetId, setEditSelectedPresetId] = useState("");
   const [editSelectedWorkflowSteps, setEditSelectedWorkflowSteps] = useState<string[]>(task.enabledWorkflowSteps || []);
   const [editSourceIssueProvider, setEditSourceIssueProvider] = useState(task.sourceIssue?.provider ?? "");
@@ -386,8 +391,9 @@ export function TaskDetailModal({
     setEditSourceIssueRepository(task.sourceIssue?.repository ?? "");
     setEditSourceIssueExternalId(task.sourceIssue?.externalIssueId ?? "");
     setEditSourceIssueUrl(task.sourceIssue?.url ?? "");
+    setEditExecutionMode(normalizeExecutionModeValue(task.executionMode));
     setIsEditing(false);
-  }, [task.id, task.title, task.description, task.sourceIssue]);
+  }, [task.id, task.title, task.description, task.sourceIssue, task.executionMode]);
 
   useEffect(() => {
     setWorkflowEnabledSteps(task.enabledWorkflowSteps || []);
@@ -554,6 +560,7 @@ export function TaskDetailModal({
     setEditPresetMode(execModel || valModel || planModel ? "custom" : "default");
     setEditSelectedPresetId("");
     setEditSelectedWorkflowSteps(task.enabledWorkflowSteps || []);
+    setEditExecutionMode(normalizeExecutionModeValue(task.executionMode));
     setEditSourceIssueProvider(task.sourceIssue?.provider ?? "");
     setEditSourceIssueRepository(task.sourceIssue?.repository ?? "");
     setEditSourceIssueExternalId(task.sourceIssue?.externalIssueId ?? "");
@@ -573,9 +580,10 @@ export function TaskDetailModal({
     setEditSourceIssueExternalId(task.sourceIssue?.externalIssueId ?? "");
     setEditSourceIssueUrl(task.sourceIssue?.url ?? "");
     setEditPriority(normalizeTaskPriorityValue(task.priority));
+    setEditExecutionMode(normalizeExecutionModeValue(task.executionMode));
     editPendingImages.forEach((img) => URL.revokeObjectURL(img.previewUrl));
     setEditPendingImages([]);
-  }, [task.title, task.description, task.dependencies, task.priority, editPendingImages]);
+  }, [task.title, task.description, task.dependencies, task.priority, task.executionMode, editPendingImages]);
 
   const handleSave = useCallback(async () => {
     setIsSaving(true);
@@ -633,6 +641,11 @@ export function TaskDetailModal({
         updates.priority = editPriority;
       }
 
+      const currentExecutionMode = normalizeExecutionModeValue(task.executionMode);
+      if (editExecutionMode !== currentExecutionMode) {
+        updates.executionMode = editExecutionMode === "fast" ? "fast" : null;
+      }
+
       const normalizedProvider = normalizeSourceIssueText(editSourceIssueProvider);
       const normalizedRepository = normalizeSourceIssueText(editSourceIssueRepository);
       const normalizedExternalId = normalizeSourceIssueText(editSourceIssueExternalId);
@@ -718,7 +731,7 @@ export function TaskDetailModal({
         setIsSaving(false);
       }
     }
-  }, [task, editTitle, editDescription, editDependencies, editExecutorModel, editValidatorModel, editPlanningModel, editThinkingLevel, editReviewLevel, editPriority, editSelectedWorkflowSteps, editSourceIssueProvider, editSourceIssueRepository, editSourceIssueExternalId, editSourceIssueUrl, editPendingImages, addToast, projectId, onTaskUpdated]);
+  }, [task, editTitle, editDescription, editDependencies, editExecutorModel, editValidatorModel, editPlanningModel, editThinkingLevel, editReviewLevel, editPriority, editExecutionMode, editSelectedWorkflowSteps, editSourceIssueProvider, editSourceIssueRepository, editSourceIssueExternalId, editSourceIssueUrl, editPendingImages, addToast, projectId, onTaskUpdated]);
 
   const handleAutoSaveDescription = useCallback(async (description: string) => {
     try {
@@ -1274,6 +1287,8 @@ export function TaskDetailModal({
                 onReviewLevelChange={setEditReviewLevel}
                 priority={editPriority}
                 onPriorityChange={setEditPriority}
+                executionMode={editExecutionMode}
+                onExecutionModeChange={setEditExecutionMode}
                 renderBelowPrimary={(
                   <div className="form-group detail-source-edit-group">
                     <label>Source Issue</label>

packages/dashboard/app/components/TaskForm.tsx

@@ -26,6 +26,8 @@ export interface PendingImage {
   previewUrl: string;
 }
 
+type TaskExecutionModeSelection = "standard" | "fast";
+
 export interface TaskFormProps {
   mode: "create" | "edit";
 
@@ -78,6 +80,8 @@ export interface TaskFormProps {
   // Review level (0=None, 1=Plan Only, 2=Plan and Code, 3=Full)
   reviewLevel?: number;
   onReviewLevelChange?: (value: number) => void;
+  executionMode?: TaskExecutionModeSelection;
+  onExecutionModeChange?: (value: TaskExecutionModeSelection) => void;
 
   // AI-assisted creation callbacks (create mode only)
   onPlanningMode?: (initialPlan: string) => void;
@@ -133,6 +137,8 @@ export function TaskForm({
   autoExpandMoreOptionsOnSelection = true,
   reviewLevel,
   onReviewLevelChange,
+  executionMode,
+  onExecutionModeChange,
 }: TaskFormProps) {
   const hasInitialMoreOptions =
     (hideDependencies ? false : dependencies.length > 0) ||
@@ -144,7 +150,8 @@ export function TaskForm({
     validatorModel !== "" ||
     (planningModel || "") !== "" ||
     (thinkingLevel || "") !== "" ||
-    reviewLevel !== undefined;
+    reviewLevel !== undefined ||
+    executionMode === "fast";
 
   const [showDepDropdown, setShowDepDropdown] = useState(false);
   const [showMoreOptions, setShowMoreOptions] = useState(
@@ -208,7 +215,8 @@ export function TaskForm({
     validatorModel !== "" ||
     (planningModel || "") !== "" ||
     (thinkingLevel || "") !== "" ||
-    reviewLevel !== undefined;
+    reviewLevel !== undefined ||
+    executionMode === "fast";
 
   // Auto-select preset by size (create mode only)
   useEffect(() => {
@@ -876,6 +884,21 @@ export function TaskForm({
             </select>
           </div>
         )}
+        {onExecutionModeChange && executionMode !== undefined && (
+          <div className="model-select-row">
+            <label htmlFor="task-execution-mode" className="model-select-label">Execution mode</label>
+            <select
+              id="task-execution-mode"
+              data-testid="task-form-execution-mode-select"
+              value={executionMode}
+              onChange={(e) => onExecutionModeChange(e.target.value as TaskExecutionModeSelection)}
+              disabled={disabled}
+            >
+              <option value="standard">Standard</option>
+              <option value="fast">Fast</option>
+            </select>
+          </div>
+        )}
         {modelsLoading ? (
           <div className="model-selector-loading">Loading models…</div>
         ) : availableModels.length === 0 ? (

packages/dashboard/app/components/__tests__/TaskDetailModal.test.tsx

@@ -4764,6 +4764,83 @@ describe("TaskDetailModal", () => {
       });
     });
 
+    it("sends executionMode: \"fast\" when changed from standard to fast", async () => {
+      const { updateTask } = await import("../../api");
+      const mockUpdate = vi.mocked(updateTask);
+      mockUpdate.mockResolvedValue({ id: "FN-001" } as Task);
+
+      const { container } = render(
+        <TaskDetailModal
+          task={makeTask({ id: "FN-001", column: "triage", title: "Test", description: "Desc", executionMode: "standard" })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(container.querySelector(".modal-edit-btn")!);
+      fireEvent.change(screen.getByTestId("task-form-execution-mode-select"), { target: { value: "fast" } });
+      fireEvent.click(screen.getByText("Save"));
+
+      await waitFor(() => {
+        expect(mockUpdate).toHaveBeenCalledWith("FN-001", { executionMode: "fast" }, undefined);
+      });
+    });
+
+    it("sends executionMode: null when changed from fast to standard", async () => {
+      const { updateTask } = await import("../../api");
+      const mockUpdate = vi.mocked(updateTask);
+      mockUpdate.mockResolvedValue({ id: "FN-001" } as Task);
+
+      const { container } = render(
+        <TaskDetailModal
+          task={makeTask({ id: "FN-001", column: "triage", title: "Test", description: "Desc", executionMode: "fast" })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(container.querySelector(".modal-edit-btn")!);
+      fireEvent.change(screen.getByTestId("task-form-execution-mode-select"), { target: { value: "standard" } });
+      fireEvent.click(screen.getByText("Save"));
+
+      await waitFor(() => {
+        expect(mockUpdate).toHaveBeenCalledWith("FN-001", { executionMode: null }, undefined);
+      });
+    });
+
+    it("omits executionMode from update payload when unchanged", async () => {
+      const { updateTask } = await import("../../api");
+      const mockUpdate = vi.mocked(updateTask);
+      mockUpdate.mockResolvedValue({ id: "FN-001" } as Task);
+
+      const { container } = render(
+        <TaskDetailModal
+          task={makeTask({ id: "FN-001", column: "triage", title: "Test", description: "Desc", executionMode: "fast" })}
+          onClose={noop}
+          onMoveTask={noopMove}
+          onDeleteTask={noopDelete}
+          onMergeTask={noopMerge}
+          onOpenDetail={noopOpenDetail}
+          addToast={noop}
+        />,
+      );
+
+      fireEvent.click(container.querySelector(".modal-edit-btn")!);
+      fireEvent.click(screen.getByText("Save"));
+
+      await waitFor(() => {
+        expect(mockUpdate).not.toHaveBeenCalled();
+      });
+    });
+
     it("renders normalized priority in detail metadata", () => {
       render(
         <TaskDetailModal

packages/dashboard/app/components/__tests__/TaskForm.test.tsx

@@ -169,6 +169,41 @@ describe("TaskForm", () => {
     expect(screen.getByText(/Model Configuration/i)).toBeTruthy();
   });
 
+  it("renders execution mode selector only when execution mode props are provided", () => {
+    const { rerender, props } = renderTaskForm();
+
+    fireEvent.click(screen.getByTestId("task-form-more-options-toggle"));
+    expect(screen.queryByTestId("task-form-execution-mode-select")).toBeNull();
+
+    rerender(
+      <TaskForm
+        {...props}
+        executionMode="standard"
+        onExecutionModeChange={vi.fn()}
+      />,
+    );
+
+    const executionModeSelect = screen.getByTestId("task-form-execution-mode-select") as HTMLSelectElement;
+    expect(executionModeSelect).toBeTruthy();
+
+    const options = Array.from(executionModeSelect.options).map((option) => option.value);
+    expect(options).toEqual(["standard", "fast"]);
+  });
+
+  it("calls onExecutionModeChange when execution mode selection changes", () => {
+    const onExecutionModeChange = vi.fn();
+
+    renderTaskForm({
+      executionMode: "standard",
+      onExecutionModeChange,
+    });
+
+    fireEvent.click(screen.getByTestId("task-form-more-options-toggle"));
+    fireEvent.change(screen.getByTestId("task-form-execution-mode-select"), { target: { value: "fast" } });
+
+    expect(onExecutionModeChange).toHaveBeenCalledWith("fast");
+  });
+
   it("renders priority select with default normal value when enabled", () => {
     renderTaskForm({ onPriorityChange: vi.fn() });