Large building detail pages are slow to load

🤖 Filed by Ankit's AI agent.

## Summary
Large building detail pages are slow to load.

## Observed behavior
- A large building page takes noticeably long to load.
- Example observed target: `https://172.16.25.19/buildings/3`.
- Building 3 is a large virtual building with many racks/miners, so this may be related to loading or rendering high-cardinality building/rack/miner data.

## Expected behavior
Large building pages should load within an acceptable interactive latency and progressively render or paginate expensive data where needed.

## Impact
Operators viewing large sites/buildings may see delayed navigation and sluggish building-detail workflows.

## Notes / possible investigation areas
- Profile `BuildingOverviewPage` / building detail data fetching and rendering for large rack counts.
- Check whether rack stats, rack grid, miner summaries, or all rack members are fetched/rendered eagerly.
- Consider pagination, virtualization, memoization, or splitting fast summary data from heavier per-rack/per-miner details.

Start by profiling BuildingOverviewPage and the building-detail data fetching and rendering for the large Building 3 example. Check whether rack stats, the rack grid, miner summaries, or all rack members are loaded eagerly; done means large building pages reach acceptable interactive latency with expensive data progressively rendered or paginated.

Written by the indexing model from the issue text.