refactor: rename ws adapter to server across codebase

'ws' conflated storage mode with transport protocol (WebSocket). Renamed for
clarity: the adapter talks the self-hosted server (src/storage/server.js), which
happens to use WebSocket for realtime — but the name should describe what it
connects to, not how.

Renames:
- src/storage/ws.js -> server.js
- createWsStorage() -> createServerStorage()
- storage mode 'ws' -> 'server'
- REACT_APP_BACKEND_WS -> REACT_APP_BACKEND_REALTIME_URL
- factory param wsUrl -> realtimeUrl
- server/tests/ws-*.test.js -> server-*.test.js

Kept literal: 'ws' npm package, ws:// protocol URLs, /ws WebSocket endpoint.
Transport is accurate there; only storage-naming changed.

Updated all docs (DEVELOPMENT, TESTING, REWORK_PLAN, GLOSSARY, TODO), scripts
(dev-start.sh, replay-combat.js), factory + ESM tests. 204 tests green.

server/tests/server-contract.test.js

@@ -0,0 +1,34 @@
+// Layer 2 test: exercise server.js storage adapter against a LIVE backend.
+// Complements Layer 1 (App + firebase mock) which proves App call shape but
+// never touches ws.js. This catches translation bugs in the adapter.
+//
+// Runs the shared storage contract (same spec memory/firebase satisfy) against
+// createServerStorage pointed at an ephemeral backend instance. A FRESH backend is
+// spun up per test to guarantee isolation (backend has no reset endpoint yet).
+
+'use strict';
+
+const path = require('path');
+const os = require('os');
+const { createServer } = require('../index');
+const { createServerStorage } = require('../../src/storage/server');
+const { runStorageContract } = require('../../src/storage/contract');
+
+// Factory: fresh backend (unique sqlite file) + storage pointed at it.
+// Disposing the storage closes the backend so each test is fully isolated.
+async function makeStorage() {
+  const dbPath = path.join(os.tmpdir(), `ws-contract-${Date.now()}-${Math.random().toString(36).slice(2)}.sqlite`);
+  const handle = createServer({ dbPath, port: 0 });
+  await new Promise((resolve, reject) => {
+    handle.server.on('error', reject);
+    handle.server.listen(0, resolve);
+  });
+  const port = handle.server.address().port;
+  const baseUrl = `http://127.0.0.1:${port}`;
+  const wsUrl = `ws://127.0.0.1:${port}/ws`;
+  const storage = createServerStorage({ baseUrl, realtimeUrl: wsUrl });
+  storage.dispose = (done) => handle.close(done);
+  return storage;
+}
+
+runStorageContract('server (live backend)', makeStorage);