- Extract assist runtime (prompt building, response parsing, finalize)
from the worker into kol_assist_runtime so the sync streaming path
and the async task path share the same logic.
- Add POST /kol/manage/assist/stream as a Server-Sent Events endpoint
emitting start/delta/completed/error events, and wire it to a
streamAssist helper on kolManageApi that reports ApiClientError with
the server's error envelope.
- Stream generated content live in KolPromptEditor and KolGenerateView,
switching KolPromptEditArea to a boolean aiBusy flag and refining the
generator page layout.
- Add KolAssistStreamEvent to shared types.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>