Move build display stats to its own file

[Regisle]

The main reason to do this is that it doesnt feel like this belongs where it is, its hard for new contributors to find without running a search on the files, and this has other issues that have built up over time like duplication of entries, and splitting it off like this makes it easier to implement something like #5752 in future.

There are a few other changes that could be done but I am leaving those either for future PRs or for feedback, namely

• De-duplication of entries, specifically duplicates across multiple lists
• Better groups (rather than using an empty element to split the group, eg adding comments etc)
• White space alignment (to make pseudo columns) (do we want this?)
• More verbose functions (instead of v and o use value and output)
• Make warnFunc only return its boolean value, and store the warn string separately
• The ability to save/load custom ones from settings (eg Custom display stats #5752)