qdoc should prefer links to a type's own API rather than outside targets when encountering ambiguity

I just noticed that the link whose text is "custom delegate" on https://doc.qt.io/qt-6/qml-qtquick-controls2-monthgrid.html#details leads to the Delegate section of the Chat Tutorial instead of MonthGrid's own delegate property. To me this behaviour is wrong: it should always prioritise linking to targets that come from the type itself (or base types) before searching for other targets. Doing this would allow us to keep nice, short section titles and/or avoid the need to qualify links with the type name.