Simplify JWT Token Generation in Registry UI

[WPrintz]

Problem

The current JWT token generation experience in the Registry UI is confusing and inconsistent:

1. Sidebar "Get JWT Token" button doesn't work when logged in with admin username/password credentials
2. Two different methods exist to get tokens - sidebar button and username dropdown menu
3. Users have to discover the dropdown method when the sidebar button fails

Current Behavior

• Login with admin username/password
• Click "Get JWT Token" in sidebar menu → Does not work
• Have to use the dropdown in the Username menu bar instead

Proposed Solution

1. Single unified button in the sidebar menu for JWT token generation
2. Remove the duplicate token generation option from the user dropdown
3. Context-aware token generation - the code should detect how the user is authenticated (OAuth, username/password, etc.) and generate the appropriate token for that user context

Benefits

• Simplified UX with one clear path to get tokens
• Consistent behavior regardless of authentication method
• Less confusion for new users

Technical Notes

The implementation will need to:

• Detect the current user's authentication method/context
• Generate tokens appropriately based on that context
• Update the sidebar button to handle all authentication scenarios
• Remove the redundant dropdown option