test: enhance test setup and infrastructure

- Improve global test setup with better mock implementations
- Add intelligent console noise suppression for cleaner test output
- Enhance browser API mocking for better test compatibility
- Update test utilities for improved reliability
- Fix fetch mock type issues for proper Jest compatibility

This improves the overall testing experience and reduces noise in test output.

tests/setup.ts

@@ -108,7 +108,7 @@ global.fetch = jest
   .fn()
   .mockResolvedValue(
     createMockResponse() as unknown as Response
-  ) as jest.MockedFunction<typeof fetch>;
+  ) as unknown as jest.MockedFunction<typeof fetch>;
 
 // Mock FormData with proper implementation
 class MockFormDataImpl implements MockFormData {
@@ -362,6 +362,7 @@ const SUPPRESSED_PATTERNS = [
   '📧 Mailgun Service',
   'Failed to send verification email',
   'Email sending failed',
+  'Configured for production with domain:',
 
   // Auth flow logging
   '🔐 Login attempt for:',
@@ -370,10 +371,17 @@ const SUPPRESSED_PATTERNS = [
   '🔍 Comparing passwords:',
   '❌ Password mismatch',
   '✅ Login successful for:',
+  'Registration failed: User already exists',
+  'Password mismatch',
+  'User not found for email:',
 
   // Database warnings
   'CouchDB connection',
   'Mock database operation',
+
+  // JSDOM navigation warnings
+  'Error: Not implemented: navigation',
+  'Not implemented: navigation (except hash changes)',
 ];
 
 const shouldSuppressMessage = (message: string): boolean => {