feat: implement flash messages system with auto-dismiss notifications

- Add flash message helper and styles for consistent notifications
- Replace Devise error messages with flash-based notifications
- Add dashboard page with event statistics
- Configure SMTP settings for development and production
- Update authentication controllers to use flash messages
- Add JavaScript controller for auto-dismiss functionality

.env.example

@@ -29,6 +29,15 @@ SMTP_PORT=1025
 SMTP_AUTHENTICATION=plain
 SMTP_ENABLE_STARTTLS=false
 
+# Production SMTP Configuration (set these in .env.production)
+# SMTP_ADDRESS=smtp.example.com
+# SMTP_PORT=587
+# SMTP_USERNAME=your_smtp_username
+# SMTP_PASSWORD=your_smtp_password
+# SMTP_AUTHENTICATION=plain
+# SMTP_DOMAIN=example.com
+# SMTP_STARTTLS=true
+
 # Application variables
 STRIPE_API_KEY=1337