feat: Support running machine-exec in ubi-based containers

[RomanNikitenko]

What does this PR do?

The che-machine-exec image now ships platform-specific binaries for UBI 8, UBI 9, and Alpine (musl), enabling FIPS-compliant execution in glibc-based containers.

Previously the image contained only a single Alpine/musl binary. While it worked in UBI containers (as a static build), it bypassed the host's crypto stack. Now each binary is built natively with CGO_ENABLED=1 against the target platform's glibc, ensuring proper FIPS compliance.

The final image layout:

• /go/bin/che-machine-exec — Alpine/musl (default entrypoint, backward-compatible)
• /go/ubi8/bin/che-machine-exec — UBI 8 (glibc, OpenSSL 1.x)
• /go/ubi9/bin/che-machine-exec — UBI 9 (glibc, OpenSSL 3.x)

Consumers (e.g. che-code's assembly.Dockerfile) can now COPY the appropriate binary into each checode assembly directory, so entrypoint-volume.sh picks the correct one at runtime based on the detected platform.

What issues does this PR fix?

• Machine-exec does not work for ubi-based images che#23648
• https://redhat.atlassian.net/browse/CRW-11626

How to test this PR?

Create machine-exec terminal using Terminal => New Terminal (Select a Container)

I've built image with current PR changes and applied it for the che-code editor: che-incubator/che-code#748

I used the following links to start a workspace and test machine-exec:

• ubi8-minimal:latest
• ubi9-minimal:latest
• ubi10-minimal:latest
• node:22-alpine3.22

[tolusha]

Hi! I'm che-ai-assistant — I help with your pull requests.

Available commands:

• /che-ai-assistant generate-che-doc — Generate a documentation PR based on this PR's changes
• /che-ai-assistant ok-pr-review — Run a comprehensive PR review (summary, code review, deep review, impact analysis)
• /che-ai-assistant check-pr-test-failures — Analyze failing CI checks, identify root causes, and suggest fixes
• /che-ai-assistant help — Show this help message