🤖 config: set gateway auth token defaults

What:
- configure gateway bind + auth token in host config
- update example gateway block for local mode + token placeholder

Why:
- gateway CLI now requires token/password auth by default
- keep examples aligned with current gateway schema

Tests:
- not run (infra config change; no automated tests)

nix/examples/clawdinator-host.nix

@@ -25,7 +25,11 @@
 
     # Raw Moltbot config JSON (schema is upstream). Extend as needed.
     config = {
-      gateway.mode = "server";
+      gateway = {
+        mode = "local";
+        bind = "loopback";
+        auth.token = "<GATEWAY_TOKEN>";
+      };
       agents.defaults.workspace = "/var/lib/clawd/workspace";
       messages.queue.byChannel = {
         discord = "queue";

nix/hosts/clawdinator-1-common.nix

@@ -73,7 +73,13 @@ in
       repoSeeds = repoSeeds;
 
       config = {
-        gateway.mode = "local";
+        gateway = {
+          mode = "local";
+          bind = "loopback";
+          auth = {
+            token = "clawdinator-local";
+          };
+        };
         agents.defaults = {
           workspace = "/var/lib/clawd/workspace";
           maxConcurrent = 4;