Show other homes' face-room lines as bubbles at once, never in the composer queue - #466

Fixes #455

What / why. In a face-to-face room, another person's line (postHuman) or another home's approved Bot reply (postRemote) that arrived while this home's group Session was mid-turn was followuped, so DSH parked it in the composer queue: raw [Group post from …] text, steerable with Cmd/Ctrl+Enter, and only drawn as a bubble after the turn. The receiving side also joined a person's typed line breaks (Markdown soft breaks).

• groups.js postToRoom: a post from elsewhere (human / remote) while the room agent is running is held instead of queued. The running round (rt.roomProgress) shows it at once as that person's bubble (personReply) or the friend's Bot bubble (kind: 'remote', kept out of round reports); a Bot line is logged then, so the Bots still to speak see it (a person's line is already logged by applyFaceLine). After agent.whenIdle() it is followuped with shown: true, so its own round routes it by the existing rules (who answers is unchanged), while group_relay neither draws nor logs it a second time. With no round running it is only held and then goes exactly as before.
• turns.js: carries shown onto the queued room item. cells.js: a trigger with shown: true draws nothing (no duplicate bubble).
• styles.js: .bt-person-msg .bt-bubble :is(p,li){white-space:pre-line}, so a person's line keeps its line breaks, matching the sender's own pre-wrap bubble.
• Docs: core-host / core-client; changelog fragment 455-face-room-other-home-lines.fixed.md.

Test.

• core/test/rounds.test.js #455: while the round runs, a 3-line peer line and another home's Bot line land in the running round's replies at once (line breaks intact, no header), nothing is queued in the Session, the Bot line is logged once; after idle both are delivered with shown: true, and the next relay neither redraws nor re-logs them. Fails on main (the lines sit in the queue).
• core/test/face-people.test.js #455: a shown trigger draws nothing (an unshown one does); the pre-line rule is in CONVERSATION_CSS and the bundle.
• ARCH_DOCS_BASE=origin/main TZ=UTC npm run verify: pass (core 1022, social 282, tree 80, timeline 80, scripts 88, interop 37, live-e2e 16; 0 failures).
• Not run: live two-home face room on the Mac instances.

Risk tier: T2 (estimate, matches the risk-gate report; the controller sets the label)