fix(deploy): resolve Docker startup and CSRF issues

- Rename TASKPLANER_DATA_DIR to DATA_DIR (avoid adapter-node envPrefix conflict)
- Add TASKPLANER_ORIGIN for CSRF protection in docker-compose.yml
- Add automatic database schema initialization on startup
- Add Playwright E2E tests for Docker deployment verification
- Update .env.example with correct variable names

Fixes container restart loop and 403 errors on form submission.

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

playwright.config.ts

@@ -0,0 +1,20 @@
+import { defineConfig } from '@playwright/test';
+
+export default defineConfig({
+	testDir: './tests',
+	fullyParallel: true,
+	forbidOnly: !!process.env.CI,
+	retries: process.env.CI ? 2 : 0,
+	workers: process.env.CI ? 1 : undefined,
+	reporter: 'html',
+	use: {
+		baseURL: process.env.BASE_URL || 'http://localhost:3000',
+		trace: 'on-first-retry'
+	},
+	projects: [
+		{
+			name: 'chromium',
+			use: { browserName: 'chromium' }
+		}
+	]
+});