Separate referral and community leaderboards

[JoaquinBN]

Summary

• split community leaderboard data from referral leaderboard data
• add a dedicated referral leaderboard endpoint and keep legacy referral URL redirecting to /referrals
• route community leaderboard calls through the category leaderboard helper while keeping compatibility aliases
• update UI labels and profile/community copy so referral points and community points are distinct

Validation

• ./env/bin/python manage.py check
• npm run build

Notes

• npm run check still fails on existing project-wide Svelte/typing issues
• focused backend referral tests are blocked by an existing seed migration expectation for albert@genlayer.foundation