This architecture has become too significant of a maintenance burden, and isn't used often enough to justify the associated maintenance cost.

This removes arm/v7 from all the build infrastructure/dockerfiles/etc. Note that arm64 targets are still widely used and well supported.

Related: linkerd/linkerd2#14308

* fix: Setup devcontainers for building aws-lc-sys

This needs a few environment variables and debian packages installed to facilitate building that package. This includes the env vars in the `just-cargo` invocation, and the packages in the rust, rust-musl, and devcontainer images.

* fix: Remove CFLAGS from just-cargo

* v48

- Update dependabot to properly scan the dev Dockerfile weekly
- Add syft, grype, oras, and cosign to the tools iamge
- Update various dependencies to be managed as OCI dependencies (for dependabot
  management)
- Update other dependencies, including Go (to 1.25) and Rust (to 1.90)
- setup-tools action:
  - Hack mandb to avoid slowness during apt installs in GitHub Actions
  - Unpack the tools binaries without doing a full docker buildx setup