feat: spreadsheet cell resizing

programs/src/desktop/compose.cpp

@@ -149,6 +149,18 @@ void gui::desktop_compose(DesktopState* ds) {
         }
     }
 
+    // Check if focused external window requests a cursor style
+    if (cur_style == CURSOR_ARROW && ds->focused_window >= 0) {
+        Window* fwin = &ds->windows[ds->focused_window];
+        if (fwin->external && fwin->ext_cursor > 0) {
+            Rect cr = fwin->content_rect();
+            if (cr.contains(ds->mouse.x, ds->mouse.y)) {
+                if (fwin->ext_cursor == 1) cur_style = CURSOR_RESIZE_H;
+                else if (fwin->ext_cursor == 2) cur_style = CURSOR_RESIZE_V;
+            }
+        }
+    }
+
     // Draw cursor last
     draw_cursor(fb, ds->mouse.x, ds->mouse.y, cur_style);
 }

programs/src/desktop/input.cpp

@@ -434,6 +434,32 @@ void gui::desktop_handle_mouse(DesktopState* ds) {
         ds->ctx_menu_open = false;
     }
 
+    // Forward continuous mouse events to focused window (hover, drag, release)
+    if (!left_pressed && ds->focused_window >= 0) {
+        Window* win = &ds->windows[ds->focused_window];
+        if (win->state != WIN_MINIMIZED && win->state != WIN_CLOSED) {
+            Rect cr = win->content_rect();
+            // Forward if mouse is over content (hover/move) or button is held/released (drag continuity)
+            if (cr.contains(mx, my) || left_held || left_released) {
+                if (win->external) {
+                    Montauk::WinEvent wev;
+                    montauk::memset(&wev, 0, sizeof(wev));
+                    wev.type = 1; // mouse
+                    wev.mouse.x = mx - cr.x;
+                    wev.mouse.y = my - cr.y;
+                    wev.mouse.scroll = 0;
+                    wev.mouse.buttons = buttons;
+                    wev.mouse.prev_buttons = prev;
+                    montauk::win_sendevent(win->ext_win_id, &wev);
+                } else if (win->on_mouse) {
+                    ev.x = mx;
+                    ev.y = my;
+                    win->on_mouse(win, ev);
+                }
+            }
+        }
+    }
+
     // Handle scroll events on focused window
     if (ev.scroll != 0 && ds->focused_window >= 0) {
         Window* win = &ds->windows[ds->focused_window];

programs/src/desktop/main.cpp

@@ -114,10 +114,11 @@ void desktop_poll_external_windows(DesktopState* ds) {
         for (int i = 0; i < ds->window_count; i++) {
             if (ds->windows[i].external && ds->windows[i].ext_win_id == extId) {
                 found = true;
-                // Update dirty flag
+                // Update dirty flag and cursor
                 if (extWins[e].dirty) {
                     ds->windows[i].dirty = true;
                 }
+                ds->windows[i].ext_cursor = extWins[e].cursor;
                 // Re-map if external app resized its buffer
                 if (extWins[e].width != ds->windows[i].content_w ||
                     extWins[e].height != ds->windows[i].content_h) {