tests: BUG-8 ws reconnect RED, BUG-7 reorder no-undo doc, ws _test accessor

server/tests/ws-reconnect.test.js: subscribe, write (fires), force-drop WS,
write again (must still fire). RED on current. wsReady=null after drop,
no reconnect, subscribers dead forever. Display frozen.

src/storage/ws.js: added _test accessor (getWs, forceDrop, getReady,
docSubs, collSubs) for reconnect test. Test-only, no behavior change.

TODO: BUG-7 (reorder no undo), BUG-8 (ws reconnect) added.

src/storage/ws.js

@@ -160,6 +160,12 @@ function createWsStorage({ baseUrl, wsUrl } = {}) {
     dispose() { if (ws) ws.close(); docSubs.clear(); collSubs.clear(); },
 
     _api: api,
+    _test: {
+      getWs: () => ws,
+      forceDrop: () => { if (ws) ws.close(); },
+      getReady: () => wsReady,
+      docSubs, collSubs,
+    },
   };
 
   return storage;