LibVT: Accept supported drag enter events

Userland/Libraries/LibVT/TerminalWidget.cpp

@@ -1115,6 +1115,13 @@ void TerminalWidget::context_menu_event(GUI::ContextMenuEvent& event)
     }
 }
 
+void TerminalWidget::drag_enter_event(GUI::DragEvent& event)
+{
+    auto const& mime_types = event.mime_types();
+    if (mime_types.contains_slow("text/plain") || mime_types.contains_slow("text/uri-list"))
+        event.accept();
+}
+
 void TerminalWidget::drop_event(GUI::DropEvent& event)
 {
     if (event.mime_data().has_urls()) {

Userland/Libraries/LibVT/TerminalWidget.h

@@ -120,6 +120,7 @@ private:
     virtual void focusin_event(GUI::FocusEvent&) override;
     virtual void focusout_event(GUI::FocusEvent&) override;
     virtual void context_menu_event(GUI::ContextMenuEvent&) override;
+    virtual void drag_enter_event(GUI::DragEvent&) override;
     virtual void drop_event(GUI::DropEvent&) override;
     virtual void leave_event(Core::Event&) override;
     virtual void did_change_font() override;