[MuseScore 4.5 Nightly] Big Time Signature behaviour in combination with hidden staves and cross staff notation

Hey everyone!

First of all thank you so much for the progress on this feature, I'm really excited about it :)
I've been taking it for a test drive on the nightly builds and I thought I'd share some problems I encountered when working with it, especially when used in a score with hidden empty staves and parts that include cross staff notation.

This particularly affects the leading space of the first note in the bar: It doesn't take into account the space occupied by the time signature. I've attached screenshot taken before and after toggling the hidden measures.

Now this issue also carries over to parts, where, if the first stave for example in a piano score is hidden, the will be issues with the placement of time signatures that require adjusting the leading space of the first note in the bar. This behaviour also carries over when the first stave's content is hidden (for instance when using cross stave notation) so it'll definitely be related to only looking at the leading space needed for the content of the first stave not of the whole system...
Additionally, courtesy time signatures also don't get their space after the bar line at the end of the system, so they just linger on after the system.

Thus far these are the issues I've encountered while using this first version of the feature, so I thought I'd share them!

Thank you very much, super excited for 4.5!