feat(tui): optimize performance by caching display lines and token counts, and improve action handling

apps/interfaces/tui/src/view/mod.rs

@@ -21,6 +21,15 @@ use zesdex_infrastructure::ToastKind;
 
 const SIDEBAR_MIN_WIDTH: u16 = 90;
 
+/// Pre-render hook: update mutable caches (display lines, token count)
+/// before the immutable `draw` pass. Called once per frame when dirty.
+///
+/// This separates cache mutation from rendering so `draw` can take
+/// `&AppStateRest` (required by `terminal.draw` closure constraints).
+pub fn pre_render(state: &mut AppStateRest) {
+    chat::pre_render_chat(state);
+}
+
 /// Top-level render entry point called once per TUI frame.
 pub fn draw(frame: &mut Frame, state: &AppStateRest) {
     let area = frame.area();