README: cluster config is the add-on's sm121_config_extra option (no second repo)

README.md

@@ -15,10 +15,9 @@ in the launcher repo.
 ## No cluster config here (on purpose)
 
 This repo is **public** — and the cluster config (`[[clusters]]` with
-private node IPs, host keys, HA entity names) is not shareable. It lives
-in the **private** `sm121/cluster-config` repo, which the HA add-on
-fetches at boot (`sm121_base_config` option) and uses as its base config.
-The Mac launcher reads its own local config.
+private node IPs, host keys, HA entity names) is not shareable. It is
+supplied as the HA add-on's `sm121_config_extra` option (raw TOML —
+HA option storage is private and on the Pi; no second repo, no PAT).
 
 ## Supersedes the old publish-bundle registry