feat: implement and deploy blind_chess MVP

- pnpm workspace: shared/server/client packages
- Server: Fastify+ws, chess.js, FSM (touch-move + hierarchy),
  per-player view filter, zod validation, rate limiting, grace-window
  disconnect handling
- Client: Svelte 5 + Vite, click-to-move board, moderator panel,
  promotion/draw dialogs
- Shared: protocol types, ModeratorText enum, geometricMoves helper
  (provably zero opponent-info leak)
- 43 tests pass (21 shared, 22 server incl. 4 real-WS integration)
- Deploy: CT 690 on node-241 (192.168.0.245), systemd-managed,
  Caddy block for chess.sethpc.xyz
- Live at https://chess.sethpc.xyz

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tsconfig.base.json

@@ -0,0 +1,18 @@
+{
+  "compilerOptions": {
+    "target": "ES2023",
+    "lib": ["ES2023"],
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "noUncheckedIndexedAccess": true,
+    "noImplicitOverride": true,
+    "skipLibCheck": true,
+    "resolveJsonModule": true,
+    "verbatimModuleSyntax": false,
+    "isolatedModules": true,
+    "declaration": true
+  }
+}