Bug#1091859: rosegarden: crashes after closing the "Mange MIDI Devices" window

[Ted Felix <ted@tedfelix.com>]

I've thrown together a new 24.12.1-stable branch:

https://sourceforge.net/p/rosegarden/git/ci/24.12.1-stable/tree/

I've fixed the invalidated iterator bug.  Please grab a snapshot from 
there and put it through its paces.  It's the best we can do for now. 
Until it goes through the Debian process and we get a new binary, we 
won't really know for sure.

I'll see if I can find additional reviewers and testers upstream.

Let me know how it goes and I'll do a 24.12.1 release.