[MU4 Task] Implement ‘Save diagnostic files‘ flow

[bkunda]

Task description This is a new feature that allows the user to quickly save relevant files as a .zip file so they can send it to developers when asking for technical support.

The design consists of:

1. New menu item in Diagnostic --> Save diagnostic files
2. New dialog (triggered by the above menu option):

N.B. The ‘Open destination folder after saving‘ checkbox would be unchecked by default

3. Clicking Save triggers the user‘s standard operating system ‘Save‘ dialog.

The files being exported will be drawn from Application Support and will include:

1. shortcuts.xml/midi_mappings.xml
2. information about found VST (see the vst folder)
3. workspaces
4. logs/dumps
5. active qml plugins

Any *.mscz files saved in this location (e.g. recovery files) will be ignored in this export.

Thanks!

@shoogle @Tantacrul @vpereverzev @RomanPudashkin feel free to re-assign to another project/label as desired :-)

[DmitryArefiev]

Implemented in #15907 (with some design changes comparing with the description)

[RomanPudashkin]

@bkunda FYI

Design changes:

1. The "Open destination folder" checkbox has been replaced by "Don't show again". It's more convenient for our testers because they will open this dialog very often (so they can hide it and save some time)
2. We will always open the destination folder after saving diagnostic files

The main points why I decided to remove the "Open destination folder" checkbox from the dialog are as follows:

• to allow us to reuse our standard dialog component (we just pass it our text and that's it), which already supports navigation/accessibility
• we don't need to create an entirely new dialog component just for one checkbox or modify the standard component to introduce more instability

The dialog can still be improved in the future

[bkunda]

2. We will always open the destination folder after saving diagnostic files

This makes perfect sense. Thank you!

[DmitryArefiev]

Retested on Win10