feat: make PBXProject.compatibilityVersion optional and add PBXProject.preferredProjectObjectVersion to support Xcode 16

[kimdv]

Resolves #837

Short description 📝

This PR will make compatibilityVersion optional. Since Xcode 16 this field isn't present anymore.
Also I added preferredProjectObjectVersion that is also part if Xcode 16 changes.

Solution 📦

I'm new to this. So I tried to see if there was ny "16.0" in a fresh and newly created Xcode project, so see if it was renamed.
Could not find any. So I made it optional, so we can decode Xcode 16 projects.

Implementation 👩‍💻👨‍💻

• Made the field optional and added preferredProjectObjectVersion
• Did run the branch against a local project and it worked

[kimdv]

It would be nice if I could get some help to tests?

[kimdv]

I just saw that preferredProjectObjectVersion in the Xcode 16 is added.
But there is no sign of it in XcodeProj. Can I add it in this PR or should it be its own?

[danieleformichelli]

Shouldn't this be an integer? do you have any example?

[kimdv]

Yes here preferredProjectObjectVersion = 77;

Changed to an Int instead.

Please review @danieleformichelli

[pepicrft]

@kimdv there seems to be legit issues in the changes. Would you mind looking into them?

[kimdv]

@kimdv there seems to be legit issues in the changes. Would you mind looking into them?

Should be fixed now.
Also I have updated the commit messages. Is that right?

[kimdv]

@pepicrft I see you changed the PR title?
Should we shorten it a little if possible?

[danieleformichelli]

@pepicrft I see you changed the PR title? Should we shorten it a little if possible?

@pepicrft I would rather change the check and don't limit the length so much

[F1248]

@kimdv, @pepicrft, @danieleformichelli, could you please take a look at #861?