Add crash_strikes and cooldown_until columns to bots table. Worker
increments strikes on crash (cooldown at 3), resets on success.
Matchmaker excludes cooldown bots from pairing, series scheduling,
and championship brackets. Fix erroneous cooldown filter on series
table in finalizeCompletedSeries (column only exists on bots).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>