feat: Support custom font domains and add font MIME type detection tests

[bhokaremoin]

Summary

This PR addresses review comments from #2068 and adds support for custom font domains in the discovery configuration.

Changes

• Font domain customization: Added fontDomains parameter to discovery config to support custom font serving domains alongside the default fonts.gstatic.com
• Improved MIME type handling: Enhanced handleIncorrectFontMimeType() function to accept and validate user-configured font domains
• Comprehensive testing: Added unit tests for font MIME type detection and integration tests to verify the function is called during asset discovery

Files Changed

• packages/core/src/utils.js - Added isKnownFontDomain() helper and updated font handling logic
• packages/core/src/network.js - Updated to pass custom font domains to MIME type handler
• packages/core/test/utils.test.js - Added unit tests for domain validation
• packages/core/test/discovery.test.js - Added integration test

Related Issues

Jira: <>

Testing

• All existing tests pass
• New unit tests validate font domain detection with both built-in and custom domains
• Integration tests confirm the function is properly called during asset discovery