Use StringChain in menu parsing whenever applicable

src/ObjLoading/Parsing/Menu/Sequence/GlobalScopeSequences.cpp

@@ -82,7 +82,7 @@ namespace menu::global_scope_sequences
             AddMatchers({
                 create.Keyword("loadMenu"),
                 create.Char('{'),
-                create.String().Capture(CAPTURE_MENU_NAME),
+                create.StringChain().Capture(CAPTURE_MENU_NAME),
                 create.Char('}'),
             });
         }

src/ObjLoading/Parsing/Menu/Sequence/ItemScopeSequences.cpp

@@ -488,7 +488,7 @@ namespace menu::item_scope_sequences
 
             AddMatchers({
                 create.KeywordIgnoreCase("execKey"),
-                create.String().Capture(CAPTURE_KEY),
+                create.StringChain().Capture(CAPTURE_KEY),
                 create.Char('{')
             });
         }

src/ObjLoading/Parsing/Menu/Sequence/MenuScopeSequences.cpp

@@ -158,7 +158,7 @@ namespace menu::menu_scope_sequences
 
             AddMatchers({
                 create.KeywordIgnoreCase("execKey"),
-                create.String().Capture(CAPTURE_KEY),
+                create.StringChain().Capture(CAPTURE_KEY),
                 create.Char('{')
             });
         }