Presence-scoped sibling restage: every tab announces the document it is
actively editing in the project presence room (PresenceState.sheetPath,
re-published on eeschema sheet navigation), and a pcbnew session connects a
sibling schematic's board-room only while a peer announces it open — instead
of eagerly holding one socket per sheet for the whole session. Works because
/files/ materializes from the ydoc, so the boot MEMFS snapshot is room-fresh;
a sheet can only drift while someone is editing it, and that someone is in
the roster. On leave the watch lingers 30s, flushes the pending restage, and
closes; without a presence room the eager mode remains as fallback.
A solo board session now holds 3 sockets (doc, presence, lib-mirror mux) —
down from 92 on an 8-project repo before this series.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01W4EzyhjhDzLdNZsFAYjz7X
b5ed68ef87