Add earlysize test for GetClientSize() before Show()

Test infrastructure to verify window sizing works correctly
when GetClientSize() is called before the window is shown.

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/e2e/earlysize.spec.ts

@@ -0,0 +1,77 @@
+// Early Size Test - Verifies GetClientSize() returns reasonable values before Show()
+// This reproduces KiCad's pattern where GetClientSize() is called in the constructor.
+import { test, expect, tryLoadApp } from './utils/fixtures';
+
+test.describe('Early GetClientSize() Tests', () => {
+
+  test('Early size test app loads successfully', async ({ page, testLogger }) => {
+    await page.goto('/standalone/earlysize/earlysize_test.html');
+    const loaded = await tryLoadApp(page);
+
+    await page.screenshot({ path: 'test-results/earlysize-01-loaded.png', fullPage: true });
+
+    const hasStartup = testLogger.consoleLogs.some(l => l.includes('[EARLYSIZE_TEST] Early size test app started'));
+
+    expect(loaded, 'Early size app should load').toBe(true);
+    expect(hasStartup, 'Startup log should be present').toBe(true);
+    expect(testLogger.errors.filter(e => !e.includes('favicon'))).toHaveLength(0);
+  });
+
+  test('GetClientSize() returns reasonable values before Show()', async ({ page, testLogger }) => {
+    await page.goto('/standalone/earlysize/earlysize_test.html');
+    const loaded = await tryLoadApp(page);
+    if (!loaded) {
+      test.skip();
+      return;
+    }
+
+    // Wait for the app to finish initialization
+    await page.waitForTimeout(500);
+
+    await page.screenshot({ path: 'test-results/earlysize-02-result.png', fullPage: true });
+
+    // Check for early client size log
+    const clientSizeLogs = testLogger.consoleLogs.filter(l => l.includes('[EARLYSIZE_TEST] Early client size:'));
+    expect(clientSizeLogs.length).toBeGreaterThan(0);
+
+    // Parse the early client size
+    const clientSizeLog = clientSizeLogs[0];
+    const clientMatch = clientSizeLog.match(/Early client size: (\d+)x(\d+)/);
+    expect(clientMatch, 'Client size log should contain dimensions').not.toBeNull();
+
+    if (clientMatch) {
+      const clientWidth = parseInt(clientMatch[1]);
+      const clientHeight = parseInt(clientMatch[2]);
+
+      // The key assertion: early client size should NOT be 20x20 or similar tiny values
+      // This is the bug we're testing for - KiCad gets 20x20 here
+      expect(clientWidth, `Early client width should be > 100 (got ${clientWidth})`).toBeGreaterThan(100);
+      expect(clientHeight, `Early client height should be > 100 (got ${clientHeight})`).toBeGreaterThan(100);
+    }
+
+    // Check for early frame size log
+    const frameSizeLogs = testLogger.consoleLogs.filter(l => l.includes('[EARLYSIZE_TEST] Early frame size:'));
+    expect(frameSizeLogs.length).toBeGreaterThan(0);
+
+    // Parse the early frame size
+    const frameSizeLog = frameSizeLogs[0];
+    const frameMatch = frameSizeLog.match(/Early frame size: (\d+)x(\d+)/);
+    expect(frameMatch, 'Frame size log should contain dimensions').not.toBeNull();
+
+    if (frameMatch) {
+      const frameWidth = parseInt(frameMatch[1]);
+      const frameHeight = parseInt(frameMatch[2]);
+
+      // Frame size should also be reasonable
+      expect(frameWidth, `Early frame width should be > 100 (got ${frameWidth})`).toBeGreaterThan(100);
+      expect(frameHeight, `Early frame height should be > 100 (got ${frameHeight})`).toBeGreaterThan(100);
+    }
+
+    // Check for PASS/FAIL result
+    const passLog = testLogger.consoleLogs.some(l => l.includes('[EARLYSIZE_TEST] PASS'));
+    const failLog = testLogger.consoleLogs.some(l => l.includes('[EARLYSIZE_TEST] FAIL'));
+
+    expect(failLog, 'Should not have FAIL log').toBe(false);
+    expect(passLog, 'Should have PASS log').toBe(true);
+  });
+});