Moves a per-profile-gateway install onto one multiplexed default gateway:
table-driven preflight (duplicate credential via the gateway's own
fingerprint; secondary port-binders without a /p/<profile>/ ingress),
--dry-run, apply (stop + uninstall each secondary's service, record it in
<default>/gateway_migration.json, flip gateway.multiplex_profiles through
the config API, restart/install the default on the same service manager,
verify served_profiles), and --standalone rollback from the manifest.
Idempotent; refuses cleanly when already multiplexed or blocked.
`hermes profile create` points at `hermes gateway restart` when a live
multiplexer is detected (the served set is snapshotted at startup).
Teknium
e2fc493427