feat: add comprehensive testing infrastructure

- Add Vitest for unit testing across all packages
- Add Playwright for E2E testing
- Add sample tests for API, Web, and Shared packages
- Configure Gitea Actions CI/CD workflows (ci, e2e, security, docker)
- Add testing documentation (TESTING.md)
- Add Gitea Actions setup guide
- Update .gitignore for test artifacts
- Add test environment configuration

packages/api/vitest.setup.ts

@@ -0,0 +1,16 @@
+import { beforeAll, afterAll } from 'vitest';
+import dotenv from 'dotenv';
+
+// Load test environment variables
+dotenv.config({ path: '.env.test' });
+
+// Global test setup
+beforeAll(() => {
+  // Setup code before all tests run
+  // e.g., initialize test database, start test server, etc.
+});
+
+afterAll(() => {
+  // Cleanup code after all tests complete
+  // e.g., close database connections, stop test server, etc.
+});