fix(ime): render preedit inline and stop Windows key-repeat from stalling redraws

frontends/rioterm/src/application.rs

@@ -460,6 +460,11 @@ impl ApplicationHandler<EventPayload> for Application<'_> {
                             // Just mark dirty — damage will be extracted from
                             // the terminal when the renderer locks it.
                             ctx_item.val.renderable_content.pending_update.set_dirty();
+                            // Skip the scheduler timer (only firable from
+                            // `about_to_wait`, which the IME key-repeat
+                            // message flood starves) and request the
+                            // paint directly. Vblank pacing stays with
+                            // the VSync worker.
                             route.request_redraw();
                         }
                     }
@@ -1940,6 +1945,22 @@ impl ApplicationHandler<EventPayload> for Application<'_> {
                         if route.window.screen.context_manager.current().ime.preedit()
                             != preedit.as_ref()
                         {
+                            // Force a full terminal repaint so the
+                            // preedit overlay's cells re-emit on the
+                            // next frame. Without this the grid keeps
+                            // its previous CPU buffers and the overlay
+                            // wouldn't refresh until something else
+                            // damages the row.
+                            route
+                                .window
+                                .screen
+                                .context_manager
+                                .current_mut()
+                                .renderable_content
+                                .pending_update
+                                .set_terminal_damage(
+                                    rio_backend::event::TerminalDamage::Full,
+                                );
                             route
                                 .window
                                 .screen

frontends/rioterm/src/context/mod.rs

@@ -116,7 +116,6 @@ impl<T: EventListener> Context<T> {
             state: self.renderable_content.cursor.state.new_from_self(),
             content: self.renderable_content.cursor.content_ref,
             content_ref: self.renderable_content.cursor.content_ref,
-            is_ime_enabled: false,
         }
     }
 }

frontends/rioterm/src/context/renderable.rs

@@ -27,7 +27,6 @@ pub struct Cursor {
     pub state: CursorState,
     pub content: char,
     pub content_ref: char,
-    pub is_ime_enabled: bool,
 }
 
 #[derive(Clone, Copy, Debug)]
@@ -145,7 +144,6 @@ impl RenderableContent {
             content: config_cursor.shape.into(),
             content_ref: config_cursor.shape.into(),
             state: CursorState::new(config_cursor.shape.into()),
-            is_ime_enabled: false,
         };
         Self::new(cursor)
     }