Cursor Bugbot caught a real hole: accept unlocks at the first variant,
so a late generation agent_done for the same session id could arrive
after Accept and close the awaited failure window early, reopening the
exact #384 gap. The SSE broadcast carries no sourceEventType, so only a
carbonize agent_done is provably accept-side; the release is now gated
on it. Copilot's wording point led somewhere real too: a carbonize-phase
failure raises the same error after the source WAS promoted, so the
toast now says "may not have been saved" and normalizes the server
message's terminal punctuation. Regression guard extended to pin both.
Prepared with AI assistance (Claude Code), directed by @pbakaus.
Co-Authored-By: Claude Code <noreply@anthropic.com>
Paul BakausandClaude Code
d0c5558960