perf(leaderboard): memoize table rows with stable keys

[abdrassulov]

📌 Description

This PR improves leaderboard performance by extracting and memoizing row components for both contributors and projects, utilizing stable keys instead of array indices.

✅ Solution

• Extracted in and wrapped it in . Used as stable keys.
• Extracted in and wrapped it in . Used uid=501(rakhimzhanabdrassulov) gid=20(staff) groups=20(staff),12(everyone),61(localaccounts),79(_appserverusr),80(admin),81(_appserveradm),98(_lpadmin),701(com.apple.sharepoint.group.1),33(_appstore),100(_lpoperator),204(_developer),250(_analyticsusers),395(com.apple.access_ftp),398(com.apple.access_screensharing),399(com.apple.access_ssh),400(com.apple.access_remote_ae) as stable keys.
• Memoized the derived top-three lists ( and ) in using .
• Added comprehensive render-count/memoization tests in and asserting that the row components are indeed memoized.

🧪 Test Results

All 21 vitest unit and integration tests compile and pass successfully!

[Jagadeeshftw]

hey @abdrassulov, thanks for the contribution! closing this one because we couldn't find a linked issue. to keep things organized: please comment on an open issue to get assigned first, then raise your pr referencing it. happy to see you back once you've been assigned!