refactor(FN-1370): merge execution settings into scheduling section

- Remove separate Execution section from settings sidebar
- Move step execution settings (runStepsInNewSessions, maxParallelSteps) into Scheduling section
- Consolidate related runtime behavior settings for better UX
- Update tests to navigate to Scheduling section instead of Execution

packages/dashboard/app/components/SettingsModal.tsx

@@ -27,7 +27,8 @@ import { applyPresetToSelection, generateUniquePresetId } from "../utils/modelPr
  *   - models: All model settings — default model (global), planning & validator models,
  *     model presets, and AI summarization (project). Rendered as sub-sections on one screen.
  *   - appearance: Theme and color settings (global)
- *   - scheduling: Concurrency, poll interval, file overlap serialization (project)
+ *   - scheduling: Concurrency, poll interval, file overlap serialization, and step execution
+ *     settings (runStepsInNewSessions, maxParallelSteps) (project)
  *   - worktrees: Worktree limits, init commands, recycling (project)
  *   - commands: Test and build command configuration (project)
  *   - merge: Auto-merge settings (project)
@@ -40,7 +41,6 @@ const SETTINGS_SECTIONS = [
   { id: "appearance", label: "Appearance", scope: "global" as const },
   { id: "scheduling", label: "Scheduling", scope: "project" as const },
   { id: "worktrees", label: "Worktrees", scope: "project" as const },
-  { id: "execution", label: "Execution", scope: "project" as const },
   { id: "commands", label: "Commands", scope: "project" as const },
   { id: "merge", label: "Merge", scope: "project" as const },
   { id: "memory", label: "Memory", scope: "project" as const },
@@ -1296,6 +1296,39 @@ export function SettingsModal({
               </label>
               <small>When enabled, tasks that modify the same files are queued serially to avoid merge conflicts</small>
             </div>
+
+            <div style={{ borderTop: "1px solid var(--border)", margin: "var(--space-lg) 0" }} />
+
+            <h5 className="settings-section-heading">Step Execution</h5>
+            <div className="form-group">
+              <label htmlFor="runStepsInNewSessions" className="checkbox-label">
+                <input
+                  id="runStepsInNewSessions"
+                  type="checkbox"
+                  checked={form.runStepsInNewSessions || false}
+                  onChange={(e) =>
+                    setForm((f) => ({ ...f, runStepsInNewSessions: e.target.checked }))
+                  }
+                />
+                Run each step in a new session
+              </label>
+              <small>Run each task step in its own fresh agent session for better isolation and error recovery. Failed steps can be retried individually.</small>
+            </div>
+            <div className="form-group">
+              <label htmlFor="maxParallelSteps">Maximum parallel steps</label>
+              <input
+                id="maxParallelSteps"
+                type="number"
+                min={1}
+                max={4}
+                value={form.maxParallelSteps ?? 2}
+                onChange={(e) =>
+                  setForm((f) => ({ ...f, maxParallelSteps: Number(e.target.value) }))
+                }
+                disabled={!form.runStepsInNewSessions}
+              />
+              <small>Maximum number of steps to run in parallel when file scopes don&apos;t overlap (1-4)</small>
+            </div>
           </>
         );
       case "worktrees":
@@ -1366,42 +1399,6 @@ export function SettingsModal({
             </div>
           </>
         );
-      case "execution":
-        return (
-          <>
-            {renderScopeBanner()}
-            <h4 className="settings-section-heading">Execution</h4>
-            <div className="form-group">
-              <label htmlFor="runStepsInNewSessions" className="checkbox-label">
-                <input
-                  id="runStepsInNewSessions"
-                  type="checkbox"
-                  checked={form.runStepsInNewSessions || false}
-                  onChange={(e) =>
-                    setForm((f) => ({ ...f, runStepsInNewSessions: e.target.checked }))
-                  }
-                />
-                Run each step in a new session
-              </label>
-              <small>Run each task step in its own fresh agent session for better isolation and error recovery. Failed steps can be retried individually.</small>
-            </div>
-            <div className="form-group">
-              <label htmlFor="maxParallelSteps">Maximum parallel steps</label>
-              <input
-                id="maxParallelSteps"
-                type="number"
-                min={1}
-                max={4}
-                value={form.maxParallelSteps ?? 2}
-                onChange={(e) =>
-                  setForm((f) => ({ ...f, maxParallelSteps: Number(e.target.value) }))
-                }
-                disabled={!form.runStepsInNewSessions}
-              />
-              <small>Maximum number of steps to run in parallel when file scopes don&apos;t overlap (1-4)</small>
-            </div>
-          </>
-        );
       case "commands":
         return (
           <>

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

@@ -1276,7 +1276,7 @@ describe("SettingsModal", () => {
     const sidebar = container.querySelector(".settings-sidebar");
     expect(sidebar).toBeTruthy();
     const navItems = sidebar!.querySelectorAll(".settings-nav-item");
-    expect(navItems.length).toBe(12);
+    expect(navItems.length).toBe(11);
 
     // Labels include scope emoji indicators (🌐 for global, 📁 for project)
     const labels = Array.from(navItems).map((el) => el.textContent);
@@ -1286,7 +1286,6 @@ describe("SettingsModal", () => {
       "🌐Appearance",
       "📁Scheduling",
       "📁Worktrees",
-      "📁Execution",
       "📁Commands",
       "📁Merge",
       "📁Memory",
@@ -2097,20 +2096,13 @@ describe("SettingsModal", () => {
     await waitFor(() => expect(addToast).toHaveBeenCalledWith("Internal server error", "error"));
   });
 
-  // --- Execution section tests ---
+  // --- Step Execution field tests (in Scheduling section) ---
 
-  it("shows Execution in sidebar", async () => {
+  it("shows runStepsInNewSessions checkbox and maxParallelSteps input in Scheduling section", async () => {
     render(<SettingsModal onClose={onClose} addToast={addToast} />);
     await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
 
-    expect(screen.getAllByText("Execution").length).toBeGreaterThanOrEqual(1);
-  });
-
-  it("shows runStepsInNewSessions checkbox and maxParallelSteps input in Execution section", async () => {
-    render(<SettingsModal onClose={onClose} addToast={addToast} />);
-    await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
-
-    fireEvent.click(screen.getByText("Execution"));
+    fireEvent.click(screen.getByText("Scheduling"));
     const checkbox = screen.getByLabelText("Run each step in a new session");
     expect(checkbox).toBeTruthy();
     expect(checkbox.getAttribute("type")).toBe("checkbox");
@@ -2124,7 +2116,7 @@ describe("SettingsModal", () => {
     render(<SettingsModal onClose={onClose} addToast={addToast} />);
     await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
 
-    fireEvent.click(screen.getByText("Execution"));
+    fireEvent.click(screen.getByText("Scheduling"));
     const input = screen.getByLabelText("Maximum parallel steps") as HTMLInputElement;
     expect(input.disabled).toBe(true);
   });
@@ -2133,7 +2125,7 @@ describe("SettingsModal", () => {
     render(<SettingsModal onClose={onClose} addToast={addToast} />);
     await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
 
-    fireEvent.click(screen.getByText("Execution"));
+    fireEvent.click(screen.getByText("Scheduling"));
     const checkbox = screen.getByLabelText("Run each step in a new session");
     fireEvent.click(checkbox);
 
@@ -2145,7 +2137,7 @@ describe("SettingsModal", () => {
     render(<SettingsModal onClose={onClose} addToast={addToast} />);
     await waitFor(() => expect(fetchSettings).toHaveBeenCalled());
 
-    fireEvent.click(screen.getByText("Execution"));
+    fireEvent.click(screen.getByText("Scheduling"));
     const checkbox = screen.getByLabelText("Run each step in a new session");
     fireEvent.click(checkbox);