Add standalone test apps and Playwright specs for wxWidgets WASM

- Add 10 standalone test apps for isolated component testing:
  - menu, toolbar, layout, aui, clipboard, filedialog, grid
  - dialog, timer, tree (3 new)
- Add 12 Playwright e2e test specs for automated testing
- Update Makefile with GL/non-GL build configurations
- Update build script to list all standalone tests
- Add WHATWORKS.md documenting KiCad wxWidgets coverage
- Update .gitignore for build artifacts

Test results:
- 79 Playwright tests pass
- wxGrid crashes (memory access out of bounds)
- wxTreeCtrl crashes (similar issue)
- wxDialog/wxMessageBox events fire but no visual popup

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/e2e/menu.spec.ts

@@ -0,0 +1,150 @@
+// wxMenuBar Tests - Menu system for KiCad
+import { test, expect, Page } from '@playwright/test';
+
+const MAIN_CANVAS = '#canvas';
+
+async function waitForApp(page: Page, timeout = 30000) {
+  await page.waitForSelector(MAIN_CANVAS, { state: 'visible', timeout });
+  await page.waitForTimeout(500);
+}
+
+async function tryLoadApp(page: Page) {
+  try {
+    await waitForApp(page, 15000);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+test.describe('wxMenuBar Tests', () => {
+
+  test('Menu test app loads successfully', async ({ page }) => {
+    const errors: string[] = [];
+    const logs: string[] = [];
+
+    page.on('pageerror', err => {
+      errors.push(`[PAGE_ERROR] ${err.message}`);
+    });
+    page.on('console', msg => {
+      logs.push(`[${msg.type()}] ${msg.text()}`);
+    });
+
+    await page.goto('/standalone/menu/menu_test.html');
+    const loaded = await tryLoadApp(page);
+
+    await page.screenshot({ path: 'test-results/menu-01-loaded.png', fullPage: true });
+
+    const hasStartupLog = logs.some(l => l.includes('wxMenuBar test app started') || l.includes('Menu test app started'));
+
+    console.log('Menu app logs:', logs.filter(l => l.includes('MENU')));
+    console.log('Menu app errors:', errors);
+    console.log('Menu app loaded:', loaded);
+    console.log('Has startup log:', hasStartupLog);
+
+    expect(loaded, 'wxMenuBar app should load successfully').toBe(true);
+    expect(errors.filter(e => !e.includes('favicon'))).toHaveLength(0);
+  });
+
+  test('Menu bar is visible', async ({ page }) => {
+    const logs: string[] = [];
+    page.on('console', msg => logs.push(msg.text()));
+
+    await page.goto('/standalone/menu/menu_test.html');
+    const loaded = await tryLoadApp(page);
+    if (!loaded) {
+      test.skip();
+      return;
+    }
+
+    await page.screenshot({ path: 'test-results/menu-02-menubar.png', fullPage: true });
+
+    // Check that app started with menu bar created
+    const hasMenuBarLog = logs.some(l => l.includes('Menu bar created') || l.includes('Menu test app started'));
+    console.log('Menu bar logs:', logs.filter(l => l.includes('menu') || l.includes('Menu')));
+
+    expect(hasMenuBarLog).toBe(true);
+  });
+
+  test('File menu can be clicked', async ({ page }) => {
+    const logs: string[] = [];
+    page.on('console', msg => logs.push(msg.text()));
+
+    await page.goto('/standalone/menu/menu_test.html');
+    const loaded = await tryLoadApp(page);
+    if (!loaded) {
+      test.skip();
+      return;
+    }
+
+    const canvas = page.locator(MAIN_CANVAS);
+    const box = await canvas.boundingBox();
+    if (!box) throw new Error('Canvas not found');
+
+    // Click on File menu (top left of menu bar, around x=30, y=10-25)
+    await page.mouse.click(box.x + 30, box.y + 15);
+    await page.waitForTimeout(500);
+
+    await page.screenshot({ path: 'test-results/menu-03-file-clicked.png', fullPage: true });
+
+    // Smoke test - no crash
+    expect(true).toBe(true);
+  });
+
+  test('Edit menu can be clicked', async ({ page }) => {
+    const logs: string[] = [];
+    page.on('console', msg => logs.push(msg.text()));
+
+    await page.goto('/standalone/menu/menu_test.html');
+    const loaded = await tryLoadApp(page);
+    if (!loaded) {
+      test.skip();
+      return;
+    }
+
+    const canvas = page.locator(MAIN_CANVAS);
+    const box = await canvas.boundingBox();
+    if (!box) throw new Error('Canvas not found');
+
+    // Click on Edit menu (next to File, around x=70, y=15)
+    await page.mouse.click(box.x + 70, box.y + 15);
+    await page.waitForTimeout(500);
+
+    await page.screenshot({ path: 'test-results/menu-04-edit-clicked.png', fullPage: true });
+
+    expect(true).toBe(true);
+  });
+
+  test('Multiple menus can be accessed', async ({ page }) => {
+    const errors: string[] = [];
+    const logs: string[] = [];
+
+    page.on('pageerror', err => errors.push(err.message));
+    page.on('console', msg => logs.push(msg.text()));
+
+    await page.goto('/standalone/menu/menu_test.html');
+    const loaded = await tryLoadApp(page);
+    if (!loaded) {
+      test.skip();
+      return;
+    }
+
+    const canvas = page.locator(MAIN_CANVAS);
+    const box = await canvas.boundingBox();
+    if (!box) throw new Error('Canvas not found');
+
+    // Click through all menus
+    const menuPositions = [30, 70, 110, 150, 190]; // File, Edit, View, Tools, Help
+    for (let i = 0; i < menuPositions.length; i++) {
+      await page.mouse.click(box.x + menuPositions[i], box.y + 15);
+      await page.waitForTimeout(300);
+    }
+
+    await page.screenshot({ path: 'test-results/menu-05-all-menus.png', fullPage: true });
+
+    console.log('\n=== MENU EVENTS ===');
+    logs.filter(l => l.includes('MENU')).forEach(l => console.log(l));
+
+    expect(errors.filter(e => !e.includes('favicon'))).toHaveLength(0);
+  });
+});