Implements Option 2 of #93. The restricted branch of broadcastPageMoved
previously resolved its audience twice — emitToAuthorizedUsers and
emitDeleteToUnauthorized each ran an independent fetchSockets +
getUserIdsWithPageAccess — leaving a race window between the two snapshots
where a socket could receive both the move and the delete (leak) or neither
(lost compensating delete).
- ws.service.ts: add emitMoveWithRestrictionSplit() that takes ONE socket
snapshot and ONE authorization resolution, then partitions the room:
authorized users get the moveTreeNode, everyone else (unauthorized +
anonymous) get the compensating deleteTreeNode. Disjoint + complete by
construction. Remove the now-unused emitToAuthorizedUsers /
emitDeleteToUnauthorized; keep private broadcastToAuthorizedUsers (still
used by emitRestrictedAwareToSpace).
- ws-tree.service.ts: broadcastPageMoved restricted branch now drives move +
delete from the single method.
- specs: assert the single method is used and that fetchSockets /
getUserIdsWithPageAccess are each called exactly once (single snapshot);
re-route ws-service.spec to emitTreeEvent after the method removal.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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