fix: Improve upload authentication and add file filtering

[NerdsCorp]

This commit addresses two major issues with the upload functionality:

1. Login Button Visibility & Token Validation:

   • Added JWT token expiration checking to detect expired tokens
   • Clear expired/invalid tokens and show login button when needed
   • Force UI refresh after updating authentication status
   • Handle 401 errors by clearing token and showing login button
   • Improved error messages for authentication failures

2. File Filtering Like Package Update:

   • Added comprehensive file exclusion logic matching package update
   • Exclude DLLs, XML files, configs, logs, screenshots
   • Type-specific exclusions for client vs editor uploads
   • Handle asset packs properly (exclude packed sources for client)
   • Process .meta files to identify packed assets
   • Support for sound and music pack exclusions

The upload now behaves consistently with package update, filtering out unnecessary files and properly handling authentication state.