Root cause: in multiplex mode `_messaging_platform_payload` read enabled/
configured from the secondary profile's own never-configured config, so the
Desktop API server page printed Disabled / "needs setup" over the live
shared-listener mirror even though `/p/<profile>/v1` answered. A live
`mirrored_from` entry (only present while the shared gateway runs) now
projects as enabled + configured; own-gateway, stopped-gateway and default
profile paths are unchanged.
Red-on-base: tests/hermes_cli/test_served_profile_mirror_platforms.py::
test_messaging_card_shows_mirrored_api_server_enabled_without_local_config
fails on origin/main at `assert payload["enabled"] is True` (line 53);
green on head: 5 passed.
Profile-scope row: T7 (Desktop pooled serve, several homes per process).
Salvaged from #122165 by @Finn763 (cherry-pick, authorship preserved).
2b9fdb85d4