fix(ente): add admin config section and fix CLI flags

- Add 'internal: admins: []' section to museum.yaml so admin CLI
  commands work after adding email to the list
- Fix --no-limit flag in helper script (requires 'True' argument)
- Add admin setup step to JSON first-start notes

json/ente.json

@@ -41,7 +41,11 @@
             "type": "warning"
         },
         {
-            "text": "First-Start: Add your account to the CLI: `ente account add` (server URL: http://localhost:8080)",
+            "text": "First-Start: Add your email as admin in museum.yaml: under `internal: admins:` add your email, then `systemctl restart ente-museum`",
+            "type": "warning"
+        },
+        {
+            "text": "First-Start: Add your account to the CLI: `ente account add` (export dir: any path, e.g. /photos)",
             "type": "warning"
         },
         {
@@ -57,4 +61,4 @@
             "type": "info"
         }
     ]
-}
+}