Fix most build-time warnings
Tests still pass and the changes are relatively straightforward. I did not manually test the respective functionality, apart from the runtime Id
warning which is now gone while the KCM still starts up. Commit messages copied below for convenience and visibility.
Fix runtime warning by removing "Id" metadata from kcm_tablet
Fix various compiler/deprecation warnings without changing behavior
Add missing property READ to KDED FilterProxyModel
According to the AutoMoc warning, the property would have been invalid without this accessor. Although the actual accessor method was already defined, right there for the taking.
Thanks in advance for a review!