Important: finalize_hackathon sort has non-deterministic ties

[0xdevcollins]

Severity: Important (fairness)

The sort uses strict > comparison:

if avg > scores.get(j).unwrap() {
    // insert
}

Two teams with identical average scores are ranked by iteration order over storage — effectively arbitrary. Team A gets first prize, Team B gets second, with no defined tiebreaker.

Fix

Define a documented tiebreaker. Recommendation:

1. Higher average score wins.
2. Tie → earlier submitted_at wins (rewards early submission).
3. Still tied → more distinct judges scoring (score_count) wins.
4. Still tied → lower address hash (deterministic fallback).

Tests

• Two identical-score submissions: earlier submitter wins
• Same submission time: more judges wins
• All tied: deterministic across runs