agents fetch the hive CA from bao at boot instead of the meta flake embedding it

nix/host-modules/hive-c0re/environment.nix

@@ -278,6 +278,9 @@ in
     # environment wholesale would inherit the hive's certificate paths with it,
     # and those name a credential no agent may present.
     HIVE_AGENT_BAO_ADDR = "https://${baoCfg.domain}:${toString baoCfg.port}";
+    # The mount whose root an agent fetches to trust the swarm's services; the
+    # same value ../hive-tls.nix reads the root from.
+    HIVE_AGENT_BAO_SERVICES_PKI_MOUNT = baoDeploy.servicesPkiMountPath;
     # `%d`, not the paths themselves: the key is `0600` root-owned and this
     # daemon runs as hive-core, so it never gets read access to the original.
     # See the LoadCredential in ./default.nix.