fix: make Files lists scroll with arrow keys

kernel/src/Api/BuildNo.hpp

@@ -12,4 +12,4 @@
 
 #pragma once
 
-#define MONTAUK_BUILD_NUMBER 178
+#define MONTAUK_BUILD_NUMBER 179

programs/src/desktop/apps/filemanager/events.cpp

@@ -319,6 +319,27 @@ void filemanager_on_mouse(Window* win, MouseEvent& ev) {
     }
 }
 
+// Keep the selected row inside the visible list area so arrow-key navigation
+// scrolls the view along with the selection.
+static void filemanager_scroll_to_selected(Window* win, FileManagerState* fm) {
+    if (fm->grid_view) return;
+    if (fm->selected < 0 || fm->selected >= fm->entry_count) return;
+
+    int list_y = FM_TOOLBAR_H + FM_PATHBAR_H + FM_HEADER_H;
+    int list_h = win->content_h - list_y;
+    if (list_h <= 0) return;
+
+    int top = fm->selected * FM_ITEM_H;
+    int off = fm->scrollbar.scroll_offset;
+    if (top < off) off = top;
+    else if (top + FM_ITEM_H > off + list_h) off = top + FM_ITEM_H - list_h;
+
+    int max_scroll = fm->entry_count * FM_ITEM_H - list_h;
+    if (off > max_scroll) off = max_scroll;
+    if (off < 0) off = 0;
+    fm->scrollbar.scroll_offset = off;
+}
+
 void filemanager_on_key(Window* win, const montauk::abi::KeyEvent& key) {
     FileManagerState* fm = (FileManagerState*)win->app_data;
     if (!fm || !key.pressed) return;
@@ -455,6 +476,7 @@ void filemanager_on_key(Window* win, const montauk::abi::KeyEvent& key) {
         } else {
             if (fm->selected > 0) fm->selected--;
         }
+        filemanager_scroll_to_selected(win, fm);
     } else if (key.scancode == 0x50) {
         // Down arrow
         if (fm->grid_view) {
@@ -465,6 +487,7 @@ void filemanager_on_key(Window* win, const montauk::abi::KeyEvent& key) {
         } else {
             if (fm->selected < fm->entry_count - 1) fm->selected++;
         }
+        filemanager_scroll_to_selected(win, fm);
     } else if (key.scancode == 0x4B && !key.alt && fm->grid_view) {
         // Left arrow (grid view only)
         if (fm->selected > 0) fm->selected--;