Add a managed gate for in-app local automation (#40436)

## What changed

- Register the stable, requirements-only `in_app_local_automation` feature for desktop apps.
- Add the feature to the configuration schema.
- Verify that an enterprise requirement can disable local automation.

GitOrigin-RevId: 939f7f3ee15f662dc85589cd1bcc3838e4cd1287

codex-rs/core/config.schema.json

@@ -751,6 +751,9 @@
             "in_app_dictation": {
               "type": "boolean"
             },
+            "in_app_local_automation": {
+              "type": "boolean"
+            },
             "in_app_updates": {
               "type": "boolean"
             },
@@ -5724,6 +5727,9 @@
         "in_app_dictation": {
           "type": "boolean"
         },
+        "in_app_local_automation": {
+          "type": "boolean"
+        },
         "in_app_updates": {
           "type": "boolean"
         },