RegisterPending → TryRegisterPending (TryAdd instead of indexer) so
battle-id collisions return false instead of silently evicting a live
battle. MatchingBridge retries with fresh IDs on collision (max 5).
Before registering, EvictStaleForViewer removes any stale pending
battle the viewer left behind, enforcing the one-pending-per-viewer
invariant that was previously comment-asserted.
Store tests switched to per-test local stores to fix a race under
the assembly-wide ParallelScope.All.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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