New external site management. New external prober heartbeat feature.

configs/control-api.example.yaml

@@ -67,11 +67,11 @@ validators:
     os_port_id: "REPLACE_WITH_NEUTRON_PORT_ID_2"
 
 # Inbound (prober) checks are OPTIONAL: list here only the external sites
-# you actually run a `prober` on, up to 3 slots (index 1-3, matches
-# ip_queue.siteN_complete — the schema is capped at 3). Leave this list
-# empty to disable inbound checks entirely — the overall result is then
-# based on egress checks alone, and aggregation doesn't wait on any
-# prober. A partial list (e.g. just index 1) only waits on that one site.
+# you actually run a `prober` on — index is any integer >= 1, no cap on
+# how many slots you configure. Leave this list empty to disable inbound
+# checks entirely — the overall result is then based on egress checks
+# alone, and aggregation doesn't wait on any prober. A partial list (e.g.
+# just index 1) only waits on that one site.
 sites:
   - site_id: "site-1"
     index: 1