Add rustc toolchain to alpine images

[nikeee]

Description

Adds rustc and cargo. Uses host-native architecture, so should fix the below-mentioned issues for every arch except x64.

Node requires at least rust 1.82, which is available in alpine 3.22/3.23 (they currently ship 1.87).

Motivation and Context

See #2486 and #2487

Testing Details

Still building.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• I have read the CONTRIBUTING.md document.

[nikeee]

I'm currently unable to verify end-to-end that this fixes the issue as I'm getting a segfault after ~10 minutes when I try to build anything in this repository from source. But the warnings that it cannot find rustc/cargo are gone, so it will probably work. Might just run this through CI and see what happens.I don't think that it is related to the rust issue as it also happens on the main branch. Probably just my local broken docker instance.

Update:
Works:

/ # node
Welcome to Node.js v26.0.0.
Type ".help" for more information.
> Temporal
Object [Temporal] {}
> 
/ # uname -a
Linux 4da0360be3ae 7.0.0-15-generic #15-Ubuntu SMP PREEMPT_DYNAMIC Wed Apr 22 16:06:43 UTC 2026 aarch64 Linux

[MikeMcC399]

Is this necessary, given that nodejs/unofficial-builds#228 was merged?

[nikeee]

I think so, because x64-musl is pulled from the unofficial-builds while arm (and all other architectures) is built in this Dockerfile: 6027bae
It doesn't have a checksum, so I think there shouldn't be anything to download. It uses a platform-emulated arm build instead.

[MikeMcC399]

If we only consider the architectures in versions.json

      "alpine3.22": [
        "amd64",
        "arm64v8"
      ],
      "alpine3.23": [
        "amd64",
        "arm64v8"
      ],

then I guess #2476 would solve the build issue for arm64v8.

Let's wait for the amd64 build for Node.js 26.1.0 to be published first, then take it from there.

[nikeee]

Yeah, that's also a thing to consider. But I think since the backup source build should work too, we should add rust/cargo to it as well.

[nschonni]

Alternately #2476 could address this, since then both the affected Alpine builds would be using the pre-built (that you fixed).
Otherwise, I think you need to run the full update.sh to include the changes in the other Alpine images