Rebuild grid agent TUI with Ratatui dashboards

crates/metacrate-grid-agent/tests/preferences_config.rs

@@ -108,3 +108,23 @@ fn dotenv_import_is_explicit_and_preferences_panel_never_renders_secrets() {
     let _ = tui.reduce(TuiInput::PreferenceSave);
     fs::remove_dir_all(directory).unwrap();
 }
+
+#[test]
+fn preferences_form_keeps_validation_feedback_visible() {
+    let directory = temporary("validation");
+    let config = directory.join("config.yml");
+    let mut tui = OperatorTui::with_preferences(config).unwrap();
+    tui.screen = OperatorScreen::Preferences;
+    let _ = tui.reduce(TuiInput::PreferenceEditOrCommit);
+    for value in "not-a-mode".chars() {
+        let _ = tui.reduce(TuiInput::PreferenceCharacter(value));
+    }
+    let _ = tui.reduce(TuiInput::PreferenceEditOrCommit);
+    let rendered = tui.render(TuiRenderOptions {
+        width: 100,
+        height: 24,
+        color: false,
+    });
+    assert!(rendered.contains("[VALIDATION] mode must be offline, integrated, or split"));
+    fs::remove_dir_all(directory).unwrap();
+}