Implement Password Grant Flow for Authentication and Enhance User Experience

- Introduced Password Grant Flow for user authentication, allowing direct login with email and password.
- Updated `useAuth` composable to manage login and logout processes, including Single Sign-Out from Cidaas.
- Enhanced user interface with a new `UserMenu` component displaying user information and logout functionality.
- Updated homepage to show personalized greetings for logged-in users and a login prompt for guests.
- Added logout confirmation page with a countdown redirect to the homepage.
- Documented the implementation details and future enhancements for OAuth2 flows in CLAUDE.md and other relevant documentation.
- Added test credentials and guidelines for automated testing in the new TESTING.md file.

nuxt.config.ts

@@ -65,6 +65,7 @@ export default defineNuxtConfig({
       userinfoUrl: process.env.CIDAAS_USERINFO_URL,
       jwksUrl: process.env.CIDAAS_JWKS_URL,
       redirectUri: process.env.CIDAAS_REDIRECT_URI,
+      postLogoutRedirectUri: process.env.CIDAAS_POST_LOGOUT_REDIRECT_URI || process.env.APP_URL || 'http://localhost:3000',
     },
 
     // Session configuration
@@ -74,6 +75,13 @@ export default defineNuxtConfig({
       password: process.env.NUXT_SESSION_SECRET || '',
     },
 
+    // Test credentials (for automated testing only)
+    // ⚠️ ONLY use in development/staging - NEVER in production
+    testUser: {
+      email: process.env.TEST_USER_EMAIL || '',
+      password: process.env.TEST_USER_PASSWORD || '',
+    },
+
     // Public (exposed to client)
     public: {
       appUrl: process.env.APP_URL || 'http://localhost:3000',