Expose scheduled tasks in plugin details (#32272)

## What changed

- Add optional `scheduledTasks` metadata to `plugin/read` responses for remote
  plugins, including hourly, daily, weekday, and weekly schedules.
- Preserve the distinction between unavailable metadata (`null`) and a catalog
  response containing no scheduled tasks (`[]`). Local plugin details return
  `null`.
- Export the corresponding Rust, JSON Schema, and TypeScript protocol types.

## Testing

- Cover scheduled-task deserialization and propagation through `plugin/read`.
- Verify missing and empty remote metadata remain distinct.

GitOrigin-RevId: 7af223ed0a1bf6d8f054293084a73f34c6d0332d

codex-rs/tui/src/chatwidget/tests/helpers.rs

@@ -1503,6 +1503,7 @@ pub(super) fn plugins_test_detail(
             .collect(),
         app_templates: Vec::new(),
         mcp_servers: mcp_servers.iter().map(|name| (*name).to_string()).collect(),
+        scheduled_tasks: None,
     }
 }
 
@@ -1522,6 +1523,7 @@ pub(super) fn plugins_test_remote_detail(
         apps: Vec::new(),
         app_templates: Vec::new(),
         mcp_servers: Vec::new(),
+        scheduled_tasks: None,
     }
 }
 

codex-rs/tui/src/chatwidget/tests/popups_and_settings.rs

@@ -876,6 +876,7 @@ async fn plugin_detail_unmaterialized_default_uses_remote_install_path() {
                 apps: Vec::new(),
                 app_templates: Vec::new(),
                 mcp_servers: Vec::new(),
+                scheduled_tasks: None,
             },
         }),
     );