feat: add branded Installer Studio desktop workspace

Closes #5

src/apps/desktop/tests/start-screen.test.mjs

@@ -0,0 +1,49 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { displayPath, groupRecentProjects, renderStartScreen } from '../src/start-screen.ts';
+import { allowProjectTransition } from '../src/project-transition.ts';
+
+const recent = (id, year, month, day, name = id) => ({
+  id, path: `C:\\projects\\${id}\\package-project.json`, displayName: name,
+  lastOpenedAt: new Date(year, month - 1, day, 10).getTime() / 1000, available: true,
+});
+
+test('recent projects are grouped in local calendar order and searchable by name or path', () => {
+  const projects = [recent('older', 2026, 9, 30), recent('today', 2026, 10, 21), recent('month', 2026, 10, 4), recent('week', 2026, 10, 20, '패키지 도구')];
+  const now = new Date(2026, 9, 21, 18);
+  assert.deepEqual([...groupRecentProjects(projects, '', now).keys()], ['오늘', '이번 주', '이번 달', '이전']);
+  assert.equal([...groupRecentProjects(projects, '패키지', now).values()][0][0].id, 'week');
+  assert.equal([...groupRecentProjects(projects, 'PROJECTS\\month', now).values()][0][0].id, 'month');
+  assert.equal(groupRecentProjects(projects, 'not found', now).size, 0);
+});
+
+test('extended Windows paths are displayed without changing their UNC semantics', () => {
+  assert.equal(displayPath('\\\\?\\C:\\apps\\project.json'), 'C:\\apps\\project.json');
+  assert.equal(displayPath('\\\\?\\UNC\\server\\share\\project.json'), '\\\\server\\share\\project.json');
+});
+
+test('start screen has left recent projects and right actions without fabricated entries', () => {
+  const base = { projects: [], query: '', busy: false, loading: false, error: '', notice: '', recentError: '', native: true };
+  const empty = renderStartScreen(base);
+  assert.match(empty, /최근 프로젝트가 없습니다/);
+  assert.ok(empty.indexOf('recent-panel') < empty.indexOf('class="start-actions"'));
+  assert.match(empty, /data-action="open"/);
+  assert.match(empty, /data-action="new"/);
+  assert.doesNotMatch(empty, /class="sidebar"/);
+  const unsafe = { ...recent('a', 2026, 10, 21, '<img src=x onerror=alert(1)>'), available: false };
+  const html = renderStartScreen({ ...base, projects: [unsafe] });
+  assert.match(html, /&lt;img/);
+  assert.doesNotMatch(html, /<img src=x/);
+  assert.match(html, /파일을 찾을 수 없습니다/);
+});
+
+test('cancel keeps edits, discard does not save, and a save failure prevents closing', async () => {
+  let saves = 0;
+  assert.equal(await allowProjectTransition(true, async () => 'cancel', async () => { saves++; }), false);
+  assert.equal(await allowProjectTransition(true, async () => 'discard', async () => { saves++; }), true);
+  assert.equal(saves, 0);
+  await assert.rejects(allowProjectTransition(true, async () => 'save', async () => { throw new Error('RevisionConflict'); }), /RevisionConflict/);
+  assert.equal(await allowProjectTransition(true, async () => 'save', async () => { saves++; }), true);
+  assert.equal(saves, 1);
+  assert.equal(await allowProjectTransition(false, async () => { throw new Error('should not ask'); }, async () => {}), true);
+});