Add accessibility command to force full read of current location
Right now during score navigation, the screenreader will (when it's working - needs Qt 5.12.4) read information about the current note. But it doesn't include things like, the name of the current staff, the key or time signature in effect, etc. It's good we don't re-read that info on every navigation command, but there should be a way to force it to be read. It should also read bar and staff number even if these haven't changed and were thus optimized away on the previous navigation command (see #293300: Optimize screenreader info information during score navigation).