fix(slack): pass recipient_team_id to streaming API calls (#20988)

* fix(slack): pass recipient_team_id and recipient_user_id to streaming API calls

The Slack Agents & AI Apps streaming API (chat.startStream / chat.stopStream)
requires recipient_team_id and recipient_user_id parameters. Without them,
stopStream fails with 'missing_recipient_team_id' (all contexts) or
'missing_recipient_user_id' (DM contexts), causing streamed messages to
disappear after generation completes.

This passes:
- team_id (from auth.test at provider startup, stored in monitor context)
- user_id (from the incoming message sender, for DM recipient identification)

through to the ChatStreamer via recipient_team_id and recipient_user_id options.

Fixes #19839, #20847, #20299, #19791, #20337

AI-assisted: Written with Claude (Opus 4.6) via OpenClaw. Lightly tested
(unit tests pass, live workspace verification in progress).

* fix(slack): disable block streaming when native streaming is active

When Slack native streaming (`chat.startStream`/`stopStream`) is enabled,
`disableBlockStreaming` was set to `false`, which activated the app-level
block streaming pipeline. This pipeline intercepted agent output, sent it
via block replies, then dropped the final payloads that would have flowed
through `deliverWithStreaming` to the Slack streaming API — resulting in
zero replies delivered.

Set `disableBlockStreaming: true` when native streaming is active so the
final reply flows through the Slack streaming API path as intended.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Vincent Koc <vincentkoc@ieee.org>

src/slack/monitor/message-handler/dispatch.ts

@@ -199,6 +199,8 @@ export async function dispatchPreparedSlackMessage(prepared: PreparedSlackMessag
           channel: message.channel,
           threadTs: streamThreadTs,
           text,
+          teamId: ctx.teamId,
+          userId: message.user,
         });
         replyPlan.markSent();
         return;
@@ -354,7 +356,7 @@ export async function dispatchPreparedSlackMessage(prepared: PreparedSlackMessag
       skillFilter: prepared.channelConfig?.skills,
       hasRepliedRef,
       disableBlockStreaming: useStreaming
-        ? false
+        ? true
         : typeof account.config.blockStreaming === "boolean"
           ? !account.config.blockStreaming
           : undefined,