feat(FN-1073): add desktop CLI workflow and packaging support

- Add new `fn desktop` CLI command with argument handling and comprehensive command/bin tests
- Implement desktop build and hot-reload dev scripts and wire package scripts/dependencies for Electron workflows
- Add electron-builder configuration and desktop main-process/integration test coverage to stabilize packaging behavior
- Document desktop development and usage in README files and include a changeset for the published CLI package

packages/cli/src/bin.test.ts

@@ -2,6 +2,7 @@ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
 const commandMocks = vi.hoisted(() => ({
   runDashboard: vi.fn(),
+  runDesktop: vi.fn(),
   runTaskCreate: vi.fn(),
   runTaskList: vi.fn(),
   runTaskMove: vi.fn(),
@@ -52,6 +53,7 @@ const commandMocks = vi.hoisted(() => ({
 }));
 
 vi.mock("./commands/dashboard.js", () => ({ runDashboard: commandMocks.runDashboard }));
+vi.mock("./commands/desktop.js", () => ({ runDesktop: commandMocks.runDesktop }));
 vi.mock("./commands/task.js", () => ({
   runTaskCreate: commandMocks.runTaskCreate,
   runTaskList: commandMocks.runTaskList,
@@ -129,8 +131,10 @@ async function runBin(args: string[]) {
     await import("./bin.ts?test=3");
   } else if (importCounter === 4) {
     await import("./bin.ts?test=4");
-  } else {
+  } else if (importCounter === 5) {
     await import("./bin.ts?test=5");
+  } else {
+    await import("./bin.ts?test=6");
   }
 }
 
@@ -182,4 +186,13 @@ describe("bin mission command integration", () => {
     await runBin(["mission", "activate-slice", "SL-001"]);
     expect(commandMocks.runMissionActivateSlice).toHaveBeenCalledWith("SL-001", undefined);
   });
+
+  it("routes desktop flags to runDesktop", async () => {
+    await runBin(["desktop", "--dev", "--paused", "--interactive"]);
+    expect(commandMocks.runDesktop).toHaveBeenCalledWith({
+      paused: true,
+      dev: true,
+      interactive: true,
+    });
+  });
 });