Detect node architecture to enable MacOS M* (ARM-based processors) builds

[LinusDietz]

This fixes mdenet/educationplatform-docker#65

Tested on a Apple M2 Pro (Sequoia 15.7.4)

[szschaler]

Thanks, @LinusDietz. Quick question: is there a reason why you didn't go with the solution originally proposed in mdenet/educationplatform-docker#65?

[LinusDietz]

I didn't understand what the solution was concretely?

mdenet-tool-xtext: 
    platform: linux/amd64

I did actually not try that.

If there is a more straightforward way to solve it, that's great.

[Copilot]

Pull request overview

Updates the Xtext container build to install the correct Node.js binary for the build architecture, enabling successful builds on Apple Silicon (arm64) while retaining x64 compatibility.

Changes:

• Replaces a fixed linux-x64 Node.js release selection with runtime architecture detection (dpkg --print-architecture).
• Installs the appropriate Node.js tarball for linux-arm64 vs linux-x64 and standardizes the install path via a /usr/local/node symlink.
• Updates PATH to use the symlinked Node install directory.

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[szschaler]

Thanks. I haven't got a Mac, so am unsure about the solution proposed in the original issue myself. It compiles on my Linux VM, so I'll give it a spin on Github CI...

[szschaler]

In the meantime, what are your thoughts, @LinusDietz, on what CoPilot has suggested above?

[szschaler]

So, this builds successfully on GitHub CI (see mdenet/educationplatform-docker#82). Once we have formed an opinion on the Copilot comments here, I'm happy to get this integrated.

[LinusDietz]

The copilot comments feel a bit nitpicky in the context of the educational platform.

1. checking the shasum might be relevant in highly critical domains, I would keep it simple in this case and avoid including more lines in the dockerfile. (not technically wrong, but the tradeoff is not there for me to include it)
2. for the same reason, I would keep it simple and not delete the .tar.xz. I don't believe that any meaningful errors are hidden from the user if the curl fails (quite unlikely anyways).
3. the last comment on the different architectures is unrealistic, as based on my cursory market analysis any docker user on a pc/mac/server will have either arm-64 or x64.

[szschaler]

LGTM