feat: add permission profile list api (#23412)

## Why

Clients need a typed permission-profile catalog instead of
reconstructing that state from config internals.

## What changed

- Added `permissionProfile/list` to the app-server v2 protocol with
cursor pagination and optional `cwd`.
- The list response includes built-in permission profiles plus
config-defined `[permissions.<id>]` profiles from the effective config
for the request context.
- Permission profiles keep optional `description` metadata for display
purposes.
- App-server docs and schema fixtures are updated for the new RPC.

codex-rs/app-server/src/message_processor.rs

@@ -1149,6 +1149,9 @@ impl MessageProcessor {
                     .experimental_feature_list(params)
                     .await
             }
+            ClientRequest::PermissionProfileList { params, .. } => {
+                self.catalog_processor.permission_profile_list(params).await
+            }
             ClientRequest::CollaborationModeList { params, .. } => {
                 self.catalog_processor.collaboration_mode_list(params).await
             }