Automatically add a newly created feed generator to the feed management page as an active feed

Summary

When a user creates a new feed generator, it should automatically be added to their feed management page as an active feed. Currently, users must manually add newly created generators to their feed management page.

Current Behavior

1. User creates a new feed generator (via AI assistant or manually)
2. User must navigate to the feed-management page
3. User clicks the "ADD GENERATOR" button
4. User selects the generator they just created from a list
5. Generator is now active in their feed

Desired Behavior

1. User creates a new feed generator
2. Generator is automatically added to their feed management page as an active feed
3. User can immediately see events from the new generator in their feed

Benefits

• Reduces friction in the feed generator workflow
• Eliminates manual steps after generator creation
• Provides immediate feedback that the generator is working
• Improves overall user experience

Implementation Notes

• When saveFeedGenerator (or similar) is called successfully, also call the function that adds the generator to the user's active feeds
• Consider adding a checkbox option "Add to my active feeds" (checked by default) if user control is desired
• Ensure proper error handling if auto-add fails (generator should still be saved)