fix: add channel status filtering (#80706)

Summary:
- Add `openclaw channels status --channel <name>` filtering through CLI, gateway protocol, and fallback status rendering.
- Document the BlueBubbles-to-iMessage cutover path so operators can probe iMessage without starting both monitors.
- Refresh generated Swift protocol model for the new optional channel status parameter.

Verification:
- `pnpm test src/gateway/server-methods/channels.status.test.ts src/commands/channels.status.command-flow.test.ts src/cli/program/routes.test.ts -- --reporter=verbose`
- `CI=true pnpm check:docs`
- `pnpm protocol:check`
- `git diff --check`
- `node scripts/check-changelog-attributions.mjs`
- CI head `45b27e3866`: focused/docs/protocol shards green locally; GitHub broad/scanner jobs queued for runners at merge attempt time; `Real behavior proof` failure is the maintainer-ignorable external-real-proof complaint.

docs/docs.json

@@ -1050,7 +1050,7 @@
             "groups": [
               {
                 "group": "Overview",
-                "pages": ["channels/index"]
+                "pages": ["channels/index", "announcements/bluebubbles-imessage"]
               },
               {
                 "group": "Mainstream messaging",