Improve highlighting structure

- switched to a sparse delta based map
- true lazy-loading to avoid any unneccessary allocations
- fixed windows management api

include/extentions/hover.h

@@ -6,9 +6,7 @@
 #include "utils/utils.h"
 #include "windows/decl.h"
 
-TileRoot *init_hover();
-
-struct HoverBox : Window {
+struct HoverBox : Popup {
   std::string text;
   std::atomic<bool> is_markup;
   uint32_t scroll_;
@@ -24,8 +22,16 @@ struct HoverBox : Window {
   }
   void scroll(int32_t number);
   void render(std::vector<ScreenCell> &buffer, Coord size, Coord pos) override;
-  void handle_click(KeyEvent, Coord) override { this->hidden = true; };
+  void handle_click(KeyEvent ev, Coord) override {
+    if (ev.mouse_button == SCROLL_BTN && ev.mouse_state == SCROLL) {
+      this->scroll(ev.mouse_direction == SCROLL_UP ? -1 : 1);
+      return;
+    }
+    this->hidden = true;
+  };
   ~HoverBox() {};
 };
 
+HoverBox *init_hover();
+
 #endif