feat(KB-037): add smartConflictResolution setting toggle

- Add smartConflictResolution toggle to Merge section in SettingsModal\n- Implement checkbox UI with label and description\n- Add comprehensive tests for toggle behavior and state\n- Follow existing SettingsModal patterns for consistency

packages/dashboard/app/components/SettingsModal.tsx

@@ -472,6 +472,20 @@ export function SettingsModal({ onClose, addToast, initialSection }: SettingsMod
               </label>
               <small>When enabled, lock files (package-lock.json, pnpm-lock.yaml, etc.), generated files (dist/*, *.gen.ts), and trivial whitespace conflicts are resolved automatically without AI intervention. Complex code conflicts still require AI review.</small>
             </div>
+            <div className="form-group">
+              <label htmlFor="smartConflictResolution" className="checkbox-label">
+                <input
+                  id="smartConflictResolution"
+                  type="checkbox"
+                  checked={form.smartConflictResolution !== false}
+                  onChange={(e) =>
+                    setForm((f) => ({ ...f, smartConflictResolution: e.target.checked }))
+                  }
+                />
+                Smart conflict resolution
+              </label>
+              <small>When enabled, lock files (package-lock.json, pnpm-lock.yaml, etc.) are resolved using 'ours' strategy, generated files (dist/*, *.gen.ts) using 'theirs' strategy, and trivial whitespace conflicts are auto-resolved without spawning an AI agent. Complex code conflicts still require AI review.</small>
+            </div>
           </>
         );
       case "authentication":

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

@@ -14,6 +14,7 @@ const defaultSettings: Settings = {
   testCommand: "",
   buildCommand: "",
   autoResolveConflicts: true,
+  smartConflictResolution: true,
 };
 
 vi.mock("../../api", () => ({
@@ -105,6 +106,7 @@ describe("SettingsModal", () => {
     expect(screen.getByText("Auto-merge completed tasks")).toBeTruthy();
     expect(screen.getByText("Include task ID in commit scope")).toBeTruthy();
     expect(screen.getByText("Auto-resolve conflicts in lock files and generated files")).toBeTruthy();
+    expect(screen.getByText("Smart conflict resolution")).toBeTruthy();
   });
 
   it("shows Recycle worktrees checkbox in Worktrees section", async () => {
@@ -249,6 +251,67 @@ describe("SettingsModal", () => {
     expect(checkbox.checked).toBe(true);
   });
 
+  it("shows Smart conflict resolution checkbox in Merge section", async () => {
+    render(<SettingsModal onClose={onClose} addToast={addToast} />);
+    await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
+
+    fireEvent.click(screen.getByText("Merge"));
+    const checkbox = screen.getByLabelText("Smart conflict resolution");
+    expect(checkbox).toBeTruthy();
+    expect(checkbox.getAttribute("type")).toBe("checkbox");
+  });
+
+  it("toggling smartConflictResolution checkbox sends false in save payload when unchecked", async () => {
+    render(<SettingsModal onClose={onClose} addToast={addToast} />);
+    await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
+
+    fireEvent.click(screen.getByText("Merge"));
+    const checkbox = screen.getByLabelText("Smart conflict resolution");
+    // Default is checked (true), click to uncheck
+    fireEvent.click(checkbox);
+
+    fireEvent.click(screen.getByText("Save"));
+    await waitFor(() => expect(updateSettings).toHaveBeenCalledTimes(1));
+
+    const payload = (updateSettings as ReturnType<typeof vi.fn>).mock.calls[0][0];
+    expect(payload.smartConflictResolution).toBe(false);
+  });
+
+  it("smartConflictResolution defaults to enabled (true) when setting is true", async () => {
+    (fetchSettings as ReturnType<typeof vi.fn>).mockResolvedValueOnce({
+      ...defaultSettings,
+      smartConflictResolution: true,
+    });
+
+    render(<SettingsModal onClose={onClose} addToast={addToast} />);
+    await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
+
+    fireEvent.click(screen.getByText("Merge"));
+    const checkbox = screen.getByLabelText("Smart conflict resolution") as HTMLInputElement;
+    expect(checkbox.checked).toBe(true);
+  });
+
+  it("smartConflictResolution checkbox submits true in save payload when checked", async () => {
+    (fetchSettings as ReturnType<typeof vi.fn>).mockResolvedValueOnce({
+      ...defaultSettings,
+      smartConflictResolution: false,
+    });
+
+    render(<SettingsModal onClose={onClose} addToast={addToast} />);
+    await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
+
+    fireEvent.click(screen.getByText("Merge"));
+    const checkbox = screen.getByLabelText("Smart conflict resolution");
+    // Default is unchecked (false), click to check
+    fireEvent.click(checkbox);
+
+    fireEvent.click(screen.getByText("Save"));
+    await waitFor(() => expect(updateSettings).toHaveBeenCalledTimes(1));
+
+    const payload = (updateSettings as ReturnType<typeof vi.fn>).mock.calls[0][0];
+    expect(payload.smartConflictResolution).toBe(true);
+  });
+
   it("groupOverlappingFiles input has type checkbox", async () => {
     render(<SettingsModal onClose={onClose} addToast={addToast} />);
     await waitFor(() => expect(fetchSettings).toHaveBeenCalled());