Use an autoloader for the plugin's files

[acicovic]

Is your feature request related to a problem?

Recently, we had to fix a bug due to a forgotten require. @GaryJones, @chriszarate and I agree that moving to an autoloader is a good move. It will help prevent similar issues and allow for cleaner code.

Describe the solution you'd like

Implement an autoloader solution for the plugin's files.

[acicovic]

Reopening this and adding it to our Summer 2024 milestone. This had been implemented in the past, but we had to roll back due to issues.

We maybe can reuse parts of the old PR, but we should conduct more thorough testing to make sure there are no issues.

[vaurdan]

I believe this should be either part of #2426, or done before that work, since all the PHP refactoring work will very much benefit from this change. What do you think?

[acicovic]

Yes, definitely agree. I prefer this to be isolated work instead of part of #2426, to keep things as atomic as possible.

[vaurdan]

Yeah, agree! In that case, I think I will take this one before spending too much time on #2426. I think it could be a relatively easy win.

[acicovic]

Agreed!