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/db.js

@@ -10,7 +10,7 @@
 //   logs/{id}                            doc
 //
 // No shape-specific tables. Data is opaque JSON. This is the firebase mirror:
-// the adapter (src/storage/ws.js) is a thin passthrough, app logic unchanged.
+// the adapter (src/storage/server.js) is a thin passthrough, app logic unchanged.
 
 'use strict';