fix syntax highlighting not refreshing on selected text removal

src/coders/lua_parsing.cpp

@@ -80,7 +80,7 @@ public:
                 return std::string({first});
             case '-':
                 skip(1);
-                if (peekNoJump() == '-') {
+                if (hasNext() && peekNoJump() == '-') {
                     skip(1);
                     return "--";
                 }

src/graphics/ui/elements/TextBox.cpp

@@ -293,6 +293,7 @@ bool TextBox::eraseSelected() {
     }
     erase(selectionStart, selectionEnd-selectionStart);
     resetSelection();
+    onInput();
     return true;
 }