Bring the Slack adapter up to the current native streaming API surface
(chat.startStream/appendStream/stopStream, GA Oct 2025) and remove the
type-erasure workarounds.
- Remove `as unknown as Parameters<...>` casts in favor of the SDK's typed
args (ChatStartStream/AppendStream/StopStream/PostMessage/UpdateArguments).
- Stream a whole turn into ONE message: drop the per-message continuation
splitting (no documented cumulative cap; matches vercel/chat), keeping the
12k per-append chunking.
- Surface tool progress as native in-message `task_update` chunks
(task_display_mode "timeline"), degrading to `🔧` rows where
structured chunks are unavailable.
- Add opt-in AI feedback buttons via `slack({ feedback })` — a typed
context_actions/feedback_buttons row attached at stopStream, with clicks
routed adapter-locally (bypassing the engine's interaction dispatch).
- Scope recipient_user_id/recipient_team_id to channel targets only.
- Lower the native flush floor to ~600ms (appendStream Tier-4), legacy stays
800ms.
Engine: add an optional, backward-compatible RunRenderer.finish() hook called
after runAgentLoop so a turn-scoped renderer can finalize its stream.
Update package READMEs + ARCHITECTURE for the assistant pane, native streaming,
and the new onThreadStarted / setSuggestedPrompts / setTitle surface. Reverse
the slack.mdx callout that told users to delete the assistant scopes (now
required), and enable the pane in the examples/slack manifest (assistant_view +
assistant:write + assistant_thread_* events) with a dev-ex onThreadStarted
greeting and the assistant config.
JSX -> Block Kit rendering with per-element budgets and degradation,
Socket Mode ingress, opaque-id interactions (ack within 3s, run async),
chat.update message streaming with chunking, accent attachments, and
sender-profile resolution. Preserves the PoC's streaming, chunking,
and mrkdwn mechanics behind the PlatformAdapter boundary.
Alem Tuzlak