Add build cache

[Knerio]

close #163

[Copilot]

Pull request overview

This PR adds Docker build cache support to improve build performance by storing and retrieving build cache layers from a container registry.

• Adds --cache-from flag to read cache from the registry during builds
• Adds --cache-to flag to write build cache to the registry for single-image builds

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
support/helpers.sh	Adds --cache-from flag to the build_image function to pull cache from registry
.gitlab/ci/container-build.gitlab-ci.yml	Adds --cache-to flag to .single-image-build-base to push cache to registry

Comments suppressed due to low confidence (1)

.gitlab/ci/container-build.gitlab-ci.yml:48

• The .variant-image-build-base template is missing the --cache-to flag that was added to .single-image-build-base. This creates inconsistency in caching behavior - variant builds won't write to the cache registry, potentially limiting cache effectiveness for these builds. Consider adding --cache-to type=registry,ref=ghcr.io/code0-tech/reticulum/ci-cache to line 48 to match the caching strategy in .single-image-build-base.

      build_image 
      $image
      $CI_PIPELINE_ID 
      "--build-arg VARIANT=$VARIANT --output type=registry,push-by-digest=true --metadata-file manifest-${CI_JOB_ID}.json"

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[github-actions]

GitLab Pipeline Action

General information

Link to pipeline: https://gitlab.com/code0-tech/development/reticulum/-/pipelines/2187591510

Status: Passed
Duration: 6 minutes