Update CI with new CMake builds.

[enetheru]

This has been rebased onto #1730
Replaced some manual shell commands to detect changes with tj-actions/changed-files@v45
Duplicated the ci.yml into ci-scons.yml and ci-cmake.yml
conditionally run the CI depending on what files change.

This is still a WIP

[enetheru]

Boy oh boy do I dislike the worlflow of troubleshooting github actions.

Anyway I couldn't have done this in a single day without the pre-existing work of @IvanInventor's #1355 and #1452

The only remaining configuration that is not at least compiling is the iOS one, and I know how to solve it, might need @Torets #1650 rebased and updated to make it work. Or I'll have to ditch the way I generate the godot-cpp targets altogether

@Ivorforce You have some experience with macos, ,do you have any with iOS?

[Torets]

... and I know how to solve it, might need @Torets #1650 rebased and updated to make it work.

rebased it, should be ok now

[dsnopek]

Thanks!

I'm not super knowledgeable with regard to GitHub Actions, so we'll probably need to get review from others who are (like @Repiteo)

Also, we need to decide if it's OK to basically double the number of CI builds we're doing. I'm not sure if I recall correctly, but I vaguely remember discussions in the past about us sharing resources with the main Godot project, and not wanting clog up the CI? Even if that is the case, we trigger way fewer builds than Godot, so it could be fine. But something to discuss if this is actually a thing :-)

[enetheru]

There are a lot of variations, perhaps have one target for regular commit CI and then some pre-merge workflows that do a more comprehensive check.

[enetheru]

I have a working iOS build in another branch: https://github.com/enetheru/godot-cpp/actions/runs/13743880227/job/38436397352
But that relies on #1733

I have to wait and see if the single target is merged before I update these to match.