12-task TDD plan in two increments:
- Increment 1 (Tasks 1-5): announce-all-to-both + capture tally.
- Increment 2 (Tasks 6-11): client-local phantom opponent-piece layer.
Each task has exact files, complete code, and verification commands.
Server/shared tasks are TDD'd with vitest; client tasks use svelte-check
plus manual verification (no client test harness, by design).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
claude (blind_chess)