Events pagination

[butschster]

Depends on #245

Summary

This PR adds events pagination on the frontend and integrates infinite scrolling for a dynamic event stream.

The implementation is designed for a continuously updating list where new events may appear at the top, while older events are loaded incrementally as the user scrolls.

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What is implemented

• Initial page load:
  • fetches event counts per type
  • loads the first page (limit = 25) for each event type
• Requests are executed in parallel, UI updates incrementally as data arrives
• Pagination metadata (has_more, next_cursor) is used to load subsequent pages
• Infinite scrolling is implemented via IntersectionObserver
  • rootMargin = 200px is used to preload data before reaching the bottom

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Edge cases handled

• No scroll appears when content fits the screen
  → next page is loaded automatically
• Scroll stuck at the bottom when new items are prepended
  → scroll position is slightly adjusted to allow observer triggering
• Scroll height smaller than rootMargin after initial load
  → additional page is auto-loaded to prevent pagination stall

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Result

The frontend now supports stable, smooth infinite scrolling for events and scales to loading all available events without artificial limits.