fix post_set_parent doc: manager is reparentable

hive-c0re/src/dashboard.rs

@@ -2184,7 +2184,9 @@ async fn post_request_spawn(
 /// `POST /api/topology/set-parent` — operator-driven parent move.
 /// Form fields: `child` (required, agent name), `new_parent`
 /// (optional — empty / absent string ⇒ promote to root). Refuses
-/// cycles, unknown agents, and reparenting the manager. On success
+/// cycles and unknown agents. The manager is reparentable like any
+/// other agent — its privileges come from the privileged MCP socket,
+/// not its tree position. On success
 /// re-emits container snapshots so the dashboard tree repaints
 /// without a refresh.
 async fn post_set_parent(