Support direct Guardian review of recorded MCP calls (#59735)

## What changed

Extend `guardian_review` to assess recorded MCP tool calls using the current tool catalog, bindings, and approval policy without executing the call or remembering an approval. Return no assessment when policy or a remembered approval skips review, and reject tools blocked by app configuration.

## Testing

Add a scenario test that compares direct and live MCP review inputs, verifies that neither dispatches the tool, and checks that the current app approval policy can skip review.

GitOrigin-RevId: 05746dd0804a0f96d7946468701d5222171ff64f

codex-rs/app-server-protocol/src/protocol/v2/thread.rs

@@ -1775,7 +1775,7 @@ pub struct ThreadGuardianReviewParams {
 #[ts(export_to = "v2/")]
 pub struct ThreadGuardianReviewResponse {
     pub call_id: String,
-    /// Null when exec policy skips approval.
+    /// Null when current policy or a remembered approval skips review.
     pub assessment: Option<ThreadGuardianAssessment>,
 }