Scheduler: prioritize later matches to maximize gap between team activities

[Copilot]

Description

When a judging session overlaps with a match round, teams had more available match slots than needed — but the scheduler always picked the earliest ones, minimizing wait time between judging and robot game. This flips that priority: teams are now assigned to the last available matches first, maximizing gaps wherever the schedule allows.

Change

In _use_constraints(), available_matches is now iterated in reverse chronological order:

# Before: assigns teams to first available matches (shortest gaps)
available_matches = round["available_matches"]

# After: assigns teams to last available matches (largest gaps)
available_matches = list(reversed(round["available_matches"]))

This is safe because _cross_reference_match_slots already resolves shared-match conflicts between sessions before _use_constraints() runs — each session's available_matches is already exclusive to that session by the time ordering matters.

Type of change

• New feature (non-breaking change which adds functionality)

Screenshots

N/A

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• My changes generate no new warnings