Merge branch 'no-global-ops'

Don't define operators for wx types in global scope.

This results in much better error messages when the compiler gives an
error about failing to resolve a call to some operator in user code
because it doesn't list all the wx-defined operators as candidates. In
practice, this cuts down error messages from 500 (!) lines to 2 with
gcc.

See #24190.

docs/changes.txt

@@ -119,6 +119,12 @@ Changes in behaviour which may result in build errors
   compatible with the previous wxWidgets versions, but now compare values, and
   not pointers, in their Index() member function.
 
+- All operators (e.g. "==", "+", etc) on wx types are not defined in global
+  scope any more, resulting in much better error messages but also preventing
+  them from implicitly being used with types convertible to wx types. If you
+  really need to use these operators with your own types, please use explicit
+  conversions.
+
 - Due to the possibility to construct wxString from std::string_view some
   previously valid code, such as "wxstr = {"Hello", 2}", is now ambiguous.
   Please use explicit class name, e.g. "wxstr = wxString{"Hello", 2}" to