enhance(main/plutolang): rename to libpluto, use php scripts to build

[mbekkomo]

Closes #21255

[TomJo2000]

Couple questions and a bit of housekeeping, but looks mostly fine.

[TomJo2000]

Also goes without saying, please squash your commits.
Doesn't have to be an immediate thing, but do it before merge.

git rebase -i HEAD~7 you know the drill.

[TomJo2000]

If you want to rebase your feature branch locally I recommend the following.

First of, in your local fork repo, add the upstream repo as a remote.
git remote add upstream https://github.com/termux/termux-packages.git

• Stash, commit, or make a diff of the pending changes on your feature branch so its "clean".
  • git stash or git diff > branchname.diff should do the trick
• git switch master
  Fast-forward the master branch to upstream's state.
• git fetch --all -v; git rebase upstream/master
  • optionally git push to update the state of your fork as well.
• git switch <feature branch>
• git rebase master to rebase it on top of the updated master
  • if you have stashed changes or a diff, apply them (git stash pop, git apply branchname.diff)
• git push --force-with-lease=branchname

Your feature branch is now up to date.

[TomJo2000]

Couple minor nits, but I don't see any substantive blockers.

[TomJo2000]

Do remember to replace the commit message with something more appropriate.

Other than that, LGTM.