The AI "Ask" affordance (selection tooltip + prompt bar) had no response
surface on an entry's canonical `main` view: RFCView renders the human-
discussion panel there, not the chat panel, so a chat turn posted from the
reading view had nowhere to render — asking-while-reading silently did
nothing. AI chat is an editing activity (a turn can emit <change> proposals)
and only runs on an edit branch.
Option B: when Ask is invoked from main, transparently cut an edit branch via
the same dispatch as Start Contributing (promote-to-branch for active,
start-edit-branch for super-draft; idempotent — reuse an existing edit
branch), navigate onto it so the chat panel mounts, and run the question
(text + selected quote) as the branch's first chat turn once its view and
main_thread_id resolve. The turn fires from the message-load effect's
continuation (not a parallel effect) so a late message load can't clobber the
optimistic turn; a live ref keeps the latest submitChatTurn closure in reach.
Degrades gracefully: signed-out → login; a viewer who can't contribute has the
cut rejected server-side and the error surfaced (no spurious branch); asking
from a branch already, and Flag on main (human discussion thread), unchanged.
Frontend-only; the branch chat endpoints already work on a branch. SPEC §8.3
records the behavior; new RFCView unit tests + an e2e spec cover the flow.
backend 677 / frontend 66 / e2e 5 green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Ben Stull
24596842ea