Add infinite scroll to Social Web feed

[obenland]

Proposed changes:

• Implements infinite scroll functionality for the Social Web feed view
• Posts automatically load as users scroll to the bottom
• Infinite scroll is enabled by default but can be toggled off in view settings
• Data accumulation logic appends new pages instead of replacing them
• Deduplication prevents duplicate posts across pages
• Cleans up pagination footer when infinite scroll is enabled

Other information:

• Have you written new tests for your changes, if applicable? - Not applicable for this UI enhancement

Testing instructions:

1. Navigate to the Social Web feed section
2. Verify that pagination controls are hidden by default
3. Scroll to the bottom of the feed
4. Observe that the next page of posts automatically loads and appends to the list
5. Continue scrolling to verify multiple pages load seamlessly
6. Open the view settings (gear icon) and verify there's an "Enable infinite scroll" toggle
7. Disable infinite scroll and verify traditional pagination controls appear
8. Test searching - verify that search results reset to page 1 and infinite scroll works with filtered results