chore(context) Include guardian approval context (#15366)

## Summary
Include the guardian context in the developer message for approvals

## Testing
- [x] Updated unit tests

codex-rs/core/src/codex.rs

@@ -3439,6 +3439,7 @@ impl Session {
             DeveloperInstructions::from_policy(
                 turn_context.sandbox_policy.get(),
                 turn_context.approval_policy.value(),
+                turn_context.config.approvals_reviewer,
                 self.services.exec_policy.current().as_ref(),
                 &turn_context.cwd,
                 turn_context

codex-rs/core/src/context_manager/updates.rs

@@ -43,6 +43,7 @@ fn build_permissions_update_item(
     Some(DeveloperInstructions::from_policy(
         next.sandbox_policy.get(),
         next.approval_policy.value(),
+        next.config.approvals_reviewer,
         exec_policy,
         &next.cwd,
         next.features.enabled(Feature::ExecPermissionApprovals),

codex-rs/core/tests/suite/permissions_messages.rs

@@ -493,6 +493,7 @@ async fn permissions_message_includes_writable_roots() -> Result<()> {
     let expected = DeveloperInstructions::from_policy(
         &sandbox_policy,
         AskForApproval::OnRequest,
+        test.config.approvals_reviewer,
         &Policy::empty(),
         test.config.cwd.as_path(),
         false,