zephyr-lite: update base to zephyr-build v0.28.4 and rework zephyr workflows

[redzynix]

zephyr-lite dockerimage

Update base to zephyr-build v0.28.4 and add improvements to the dockerimage

• Remove python3.12 installation as it's already supplied by new
  docker base
• Remove sysroots from toolchains to free up space
• Install jsonschema and cmake
• Update SDK to 0.17.4
• Use venv for python packages

Zephyr workflows rework

Drop support of docker-run.sh wrapper used in zephyr workflows in favor of using container: image: tag that is built into github workflow syntax
Reworked workflows include:

• .github/workflows/zephyr.yml - https://github.com/thesofproject/sof/actions/runs/18163609096
• .github/workflows/sparse-zephyr.yml - https://github.com/thesofproject/sof/actions/runs/18163609031
• .github/workflows/llext.yml - https://github.com/thesofproject/sof/actions/runs/18163609061/job/51700001165

Signed-off-by: Mateusz Redzynia mateuszx.redzynia@intel.com

[Copilot]

Pull Request Overview

Update zephyr-lite to zephyr-build v0.28.4, streamline the image and CI by leveraging GitHub Actions’ container: image: support, and bump the Zephyr SDK to 0.17.4 with a Python venv for tooling.

• Upgrade base image and SDK (v0.28.4 / 0.17.4) and trim unused toolchains
• Move CI to container-based workflows; drop docker-run.sh wrapper usage
• Install cmake and jsonschema in a venv and simplify docker-build.sh

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
zephyr/docker-run.sh	Update image tag and comments to v0.28.4/SDK 0.17.4 to reflect new base.
zephyr/docker-build.sh	Remove redundant pip-based cmake install now provided by the image venv.
scripts/docker_build/zephyr_lite/Dockerfile	Switch to zephyr-build v0.28.4, prune toolchains/sysroots, add venv packages, set env, and default shell.
.github/workflows/zephyr.yml	Rework to use container image, simplify west steps/paths, and adjust build/run locations.
.github/workflows/sparse-zephyr.yml	Use container image, streamline west usage and paths, and keep sparse build inside container.
.github/workflows/llext.yml	Use container image, simplify west usage, and run builds directly without wrapper.

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[tmleman]

The workflow testing the build on Windows is using an older SDK. Can we update it as part of this PR?
https://github.com/thesofproject/sof/blob/main/.github/workflows/zephyr.yml#L286-L306

[redzynix]

The workflow testing the build on Windows is using an older SDK. Can we update it as part of this PR? main/.github/workflows/zephyr.yml#L286-L306

Updated windows zephyr sdk to 0.17.4

[abonislawski]

LGTM, thanks!

[kv2019i]

@redzynix Not blocking as we haven't been 100% systematic with the prefixes, but for future PRs, use "github: llext: change workflot to foobar" prefix for git commits that touch the github workflows. See "git log .github/" for example of past changes.

E.g. prefix "zephyr: ..." indicates you are changing the zephyr SOF implementation that lives in work/sof/zephyr, but that's not really the case in this PR.