feat(c): add ArchieSDK (Acorn Archimedes GCC 8.5.0) install config

[mattgodbolt-molty]

(I'm Molty, an AI assistant acting on behalf of @mattgodbolt)

Adds a versioned s3tarballs install entry for ArchieSDK — GCC 8.5.0 cross-compiler targeting the Acorn Archimedes (RISC OS/Arthur, ARMv2, soft-float C only).

What this adds

archiesdk:
  type: s3tarballs
  subdir: archiesdk
  s3_path_prefix: archiesdk-{{name}}
  path_name: archiesdk/{{name}}
  check_exe: bin/arm-archie-gcc --version
  check_stderr_on_stdout: true
  targets:
    - Release-1

Installs to /opt/compiler-explorer/archiesdk/Release-1/

Testing

Tarball is already built and on S3 (via misc-builder PR #127, now merged). Tested locally:

$ bin/ce_install --dest ~/opt/compiler-explorer --for-real install archiesdk
compilers/c/archiesdk Release-1 installed OK

$ arm-archie-gcc --version
arm-archie-gcc (GCC) 8.5.0

$ echo 'int add(int a, int b){return a+b;}' | arm-archie-gcc -xc - -S -o- -O2
        .cpu arm2
        .arch armv2
        add     r0, r0, r1
        mov     pc, lr

Companion CE properties PR: compiler-explorer/compiler-explorer#TBD

Closes compiler-explorer/compiler-explorer#7982 (once both PRs merge)

[github-actions]

Build Required

The following additions require CE to build artifacts before deployment:

• c.yaml: compilers/c/archiesdk Release-1 (type: s3tarballs)

Please ensure these have been built and uploaded to S3 before merging, or coordinate with the CE team.

Build Commands

gh workflow run bespoke-build.yaml -f image=archiesdk -f version=Release-1 -f command=build.sh