[Birfy]

Fixes #305

What is left of #305 after #425 (one name per Bot):

• Face room @ menu without DSH's Sessions rows (owner decision: filter in FlyBot for now; DSH request: let a plugin hide the shell's Sessions rows in a room's @ menu (replace FlyBot's filter) #422 stays open for a DSH API). DSH's built-in reference source cannot be dropped for one Session, so for a face-to-face room HeaderPill starts actions.filterFaceAtMenu, which watches that Session's trigger controller (inputTriggers.sessionOf, the one the composer uses; FlyBot already uses it for "Reference a chat"). New face-at-filter.js: a <style data-bt-face-at> hides the reference rows whose icon is session (Sessions and Subagents) and their section title, by MenuView's option ids; controller.hover moves the highlight past them in the direction of the key, so arrow keys skip them and Enter never picks a hidden row; a menu with nothing else left is dismiss()ed, so Enter sends. File rows stay. No DSH patch.
• Everyone's count in a group now counts the Bots it reaches (local members plus seated friends' Bots), with singular/plural: 1 member / 2 members (also the palette's group subtitle). Face rooms keep Every Bot in this room.
• Already on main, checked: one row per Bot in a face room (Face room @ picker: each Bot in the room once, named Person · Bot, no outside friends' Bots #339), Bot (owner) naming (One name for a friend's Bot: Bot (owner), everywhere #425), the mention chip with @, the same label on both homes and no doubled space (Face-room @ chips: one name on both homes, with @, and no doubled space (part of #305) #367/Face-room @ chips: my own bare @Chief stays my Chief whatever the seat order (#305 follow-up) #368, test mention-rule.test.js).

Tests: core/test/face-at-filter.test.js (rows and titles hidden, files and Bots kept, highlight steering both ways, dismiss when only Session rows are left, watcher clean-up), core/test/at-menu.test.js (Everyone count). Docs: docs/subsystems/core-client.md. Changelog: changelog.d/305-face-room-at-menu.fixed.md.

Ran: ARCH_DOCS_BASE=origin/main TZ=UTC npm run verify at 592d535 (core 966+ tests, social, tree, timeline, scripts, interop, live-e2e: all pass); node core/scripts/build-client.mjs --check; node scripts/ds-bot-patches.mjs check.
Not run: smoke bench; a live two-home browser check of the face-room @ menu in DSH Desktop (the CSS relies on MenuView's dsh-slash-option-<source>-<index> ids and :has(), checked against DSH 0.2.0-rc.2).

[Birfy]

Self-review (Birfy, owner's Bot)

Read the full diff at the tip against main.

• Scope matches the delegated decision on Face room @ picker lists a friend's Bot 5 times in 3 sections, 'Everyone · 1 members'; mention chip renders differently per home; Bot named 4 ways #305 (16:36 Asia/Shanghai): face-to-face room only; DSH's Sessions (and Subagents) rows plus their section title are filtered in FlyBot; nothing filed upstream, DSH request: let a plugin hide the shell's Sessions rows in a room's @ menu (replace FlyBot's filter) #422 untouched. No DSH patch: it uses the public inputTriggers.sessionOf controller (menu store, hover, dismiss) that FlyBot already uses for "Reference a chat", plus CSS by MenuView's option ids.
• The arrow-key / Enter concern of option 1 is handled: the highlight is moved past hidden rows in the key's direction, and a menu with only hidden rows is dismissed, so Enter sends rather than inserting an invisible Session reference. File rows and all Bot/person rows stay. Pending groups are left alone (DSH's Enter on a pending group is already a no-op).
• Lifecycle: the watcher starts from HeaderPill only for a face room, is re-armed when the trigger service comes up, and removes its <style> and subscription on leave; corrections run in a microtask, outside DSH's reducer.
• Everyone count: now counts Bots it reaches (local + seated friends' Bots, not humans), 1 member / N members; zh entry added; face rooms unchanged.
• Conflict surface with Held reply to a friend: held in place, decision on the bubble, Sent / Not sent after (#418) #430: only a one-line i18n.js addition (line 68, far from Held reply to a friend: held in place, decision on the bubble, Sent / Not sent after (#418) #430's hunk) and generated patch files; no edits to cells.js, sidebar.js, text.js, flybot-slots.js or plugins/social.
• Risk noted: the CSS depends on DSH MenuView's dsh-slash-option-<source>-<index> ids and :has() (checked against DSH 0.2.0-rc.2); a DSH upgrade that renames them would only bring the rows back, not break the menu. To be replaced by a DSH API (DSH request: let a plugin hide the shell's Sessions rows in a room's @ menu (replace FlyBot's filter) #422).

Verdict: PASS
Tip SHA: 592d535
Ran: ARCH_DOCS_BASE=origin/main TZ=UTC npm run verify at 592d535 (all suites pass), build-client.mjs --check, ds-bot-patches.mjs check; CI tests-ok green at the tip.
Not run: smoke bench; a live two-home browser check of the face-room @ menu in DSH Desktop.