docs: the dev-infra image needs Rosetta on Apple Silicon

"x86 only" was too strong. The image is amd64-only — proxmox-auto-install-assistant
and the HashiCorp apt repo publish no arm64 — but it builds and runs on Apple Silicon
once Docker Desktop's Rosetta emulation is on.

Under the default qemu translation pwsh starts and reports its version, then segfaults
on module discovery (uncaught target signal 11), which fails the build at
Install-Module Pester and would fail Pester at test time. With Rosetta enabled the same
Dockerfile builds to within 150 bytes of the image CI pushed for this commit, and
Invoke-Pester runs.

Worth stating explicitly because the failure is silent: the build step exits 1 with no
diagnostic output, which reads as a Dockerfile defect rather than an emulation problem.

CLAUDE.md

@@ -93,7 +93,13 @@ or delete the installed copy. (`dotnet build` writes there; only `dotnet publish
 ./publish/netstandard2.0`, which CI runs, creates `publish/`.)
 
 The integration flow needs the `dev-infra` container — the same image CI runs its jobs in
-(`tests/Dockerfile.test`, target `dev-infra`). x86 only:
+(`tests/Dockerfile.test`, target `dev-infra`).
+
+The image is amd64-only: `proxmox-auto-install-assistant` and the HashiCorp apt repo publish no
+arm64. On Apple Silicon turn on Docker Desktop's **Use Rosetta for x86_64/amd64 emulation**
+before building or running it. Under the default qemu translation `pwsh` starts but segfaults
+on module discovery, which fails the image build at `Install-Module Pester`; under Rosetta the
+same Dockerfile builds byte-equivalent to CI's.
 
 ```bash
 pve() {