pass on save info to model + ui tweaks (#14123)

Passing on more information to the model for context purposes, to
streamline image-identification.

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

@@ -6288,7 +6288,7 @@ async fn image_generation_call_adds_history_cell() {
             status: "completed".into(),
             revised_prompt: Some("A tiny blue square".into()),
             result: "Zm9v".into(),
-            saved_path: None,
+            saved_path: Some("/tmp/project/ig-1.png".into()),
         }),
     });