fix(App): colors getter returns a const pointer now

src/app/App.cpp

@@ -352,8 +352,8 @@ void registerToolType (const char *name) {
 
 #define registerSharedToolType(TYPE, NAME, METHOD) qmlRegisterSingletonType<TYPE>( \
   NAME, 1, 0, NAME, \
-  [](QQmlEngine *, QJSEngine *) -> QObject *{ \
-    QObject *object = METHOD(); \
+  [](QQmlEngine *, QJSEngine *) ->  QObject *{ \
+    QObject *object = const_cast<TYPE *>(METHOD()); \
     QQmlEngine::setObjectOwnership(object, QQmlEngine::CppOwnership); \
     return object; \
   } \

src/app/App.hpp

@@ -64,7 +64,7 @@ public:
     return mNotifier;
   }
 
-  Colors *getColors () const {
+  const Colors *getColors () const {
     return mColors;
   }
 

src/app/providers/ImageProvider.cpp

@@ -58,10 +58,7 @@ static QByteArray buildByteArrayAttribute (const QByteArray &name, const QByteAr
   return attribute;
 }
 
-static QByteArray parseFillAndStroke (
-  QXmlStreamAttributes &readerAttributes,
-  const Colors &colors
-) {
+static QByteArray parseFillAndStroke (QXmlStreamAttributes &readerAttributes, const Colors &colors) {
   static QRegExp regex("^color-([^-]+)-(fill|stroke)$");
 
   QByteArray attributes;
@@ -86,10 +83,7 @@ static QByteArray parseFillAndStroke (
   return attributes;
 }
 
-static QByteArray parseStyle (
-  QXmlStreamAttributes &readerAttributes,
-  const Colors &colors
-) {
+static QByteArray parseStyle (QXmlStreamAttributes &readerAttributes, const Colors &colors) {
   static QRegExp regex("^color-([^-]+)-style-(fill|stroke)$");
 
   QByteArray attribute;