fix(auto-reply): keep group visible replies deliverable (#75382)

Summary:
- The PR updates auto-reply message-tool availability and fallback policy, qa-channel group target support, qa-lab scenario coverage, generated config metadata, docs, and the changelog for group visible replies.

ClawSweeper fixups:
- No separate fixup commits were needed after automerge opt-in.

Validation:
- ClawSweeper review passed for head adbec93b8a.
- Required merge gates passed before the squash merge.

Prepared head SHA: adbec93b8a
Review: https://github.com/openclaw/openclaw/pull/75382#issuecomment-4357590733

Co-authored-by: Peter Steinberger <steipete@gmail.com>

docs/channels/qa-channel.md

@@ -14,7 +14,9 @@ read_when:
 - Slack-class target grammar:
   - `dm:<user>`
   - `channel:<room>`
+  - `group:<room>`
   - `thread:<room>/<thread>`
+- Shared `channel:` and `group:` conversations are surfaced to agents as group/channel room turns, so they exercise the same visible-reply and message-tool routing policy used by Discord, Slack, Telegram, and similar transports.
 - HTTP-backed synthetic bus for inbound message injection, outbound transcript capture, thread creation, reactions, edits, deletes, and search/read actions.
 - Host-side self-check runner that writes a Markdown report to `.artifacts/qa-e2e/`.