Fix weapons clearing when selecting 8th weapon in CAST VOD upload (#2710)

Co-authored-by: Claude <noreply@anthropic.com>

app/features/vods/routes/vods.new.tsx

@@ -494,7 +494,7 @@ function WeaponsField({
 											const adjustedI = i + teamSize;
 											return (
 												<WeaponSelect
-													key={i}
+													key={adjustedI}
 													isRequired
 													testId={`player-${adjustedI}-weapon`}
 													value={value[adjustedI] ?? null}