Update local option in build script to compile FTL directly

[PromoFaux]

What does this PR aim to accomplish?:

Have been meaning to do this for a while, finally found the motivation to do so.

I like that docker is smart enough to know that it can skip certain stages if the final image does not use anything from them

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[Copilot]

Copilot reviewed 1 out of 3 changed files in this pull request and generated 1 comment.

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[DL6ER]

What is the advantage compared to downloading the ready-made binaries?

Except, maybe,

• can do this even when the binaries have nit (yet) finished compiling,
• works also on unsupported platforms (well, if docker works there, at least)

[PromoFaux]

There you go, you've listed the advantages.

I can't imagine that anyone other than me ever uses it - and just sometimes I want to be able to test things before the CI has got to it.

Edit: though you make a good point... And it has me now thinking "What if I want to use a branch I am working on locally?... back to the drawing board

[yubiuser]

I'm not sure if this is really needed. The CI builds fast except of RISCV and will push the binaries after each architecture finishes. So for most it should be available within minutes.

If you want to include a local FTL branch which you need to build first - well, we have the FTL devcontainer. Moving the binary from the FTL repo to the docker repo and include it with the -l flag seems manageable.

[PromoFaux]

By the same token ./build.sh is not really needed - it just makes it easier. ;)

But comments understood and agreed with on the main - I realise that building locally in one fell swoop is more useful if they are local modifications not available from github.

Moving the binary from the FTL repo to the docker repo and include it with the -l flag seems manageable.

This step annoys me more often than it should, which was what the main goal was here 😏

I've got some ideas that I may or may not look at in future