Refresh environment dates from the configured clock (#36187)

## Why

The `<current_date>` in environment context could diverge from the clock used by current-time features, especially when a host provides an external clock.

## What changed

- Read the current time from the session's time provider whenever world state is built, and render its local date in environment context.
- Use each session's own thread ID for clock reads, including guardian sessions.
- Propagate clock-read failures through turn error events and stop before model inference.

## Testing

- Cover date updates across turns and app-server requests.
- Verify guardian clock reads use the corresponding root or guardian thread ID and do not run during prewarm.
- Verify clock failures emit an error without sending an inference request.

GitOrigin-RevId: bb7f32ccc0229b7bc6f14d7356db00bcce78066d

codex-rs/core/src/codex_thread.rs

@@ -496,7 +496,7 @@ impl CodexThread {
                 .await?;
             self.session
                 .record_context_updates_and_set_reference_context_item(step_context.as_ref())
-                .await;
+                .await?;
         }
         self.session
             .inject_no_new_turn(items, Some(turn_context.as_ref()))