mcp: move config to .mcp.json.example, gitignore real config

The real .mcp.json now contains Loki credentials for basic auth,
so it should not be committed. The example file has placeholders.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -2,6 +2,9 @@
 result
 result-*
 
+# MCP config (contains secrets)
+.mcp.json
+
 # Terraform/OpenTofu
 terraform/.terraform/
 terraform/.terraform.lock.hcl

.mcp.json.example

@@ -20,7 +20,9 @@
       "env": {
         "PROMETHEUS_URL": "https://prometheus.home.2rjus.net",
         "ALERTMANAGER_URL": "https://alertmanager.home.2rjus.net",
-        "LOKI_URL": "http://monitoring01.home.2rjus.net:3100"
+        "LOKI_URL": "https://loki.home.2rjus.net",
+        "LOKI_USERNAME": "promtail",
+        "LOKI_PASSWORD": "<password from: bao kv get -field=password secret/shared/loki/push-auth>"
       }
     },
     "homelab-deploy": {
@@ -44,4 +46,3 @@
     }
   }
 }
-