Add setup-gomplate input and install gomplate with checksum verification

[Copilot]

This issue requests support for gomplate setup in initialize-github-job, following the referenced installation approach. This PR adds a dedicated setup-gomplate field and wires in a checksum-verified install path for gomplate v5.0.0.

• Composite action updates

  • Added new input in action.yml:
    • setup-gomplate (default: false)
  • Added conditional gomplate setup steps gated by setup-gomplate == 'true'
  • Implemented install flow aligned with the requested pattern:
    • download Linux AMD64 gomplate binary
    • download release checksum file
    • extract expected hash and verify with sha256sum -c -
    • install to /usr/local/bin/gomplate
  • Added explicit failure messages for download/checksum failure paths.

• Workflow coverage

  • Extended .github/workflows/test.yml:
    • enabled setup-gomplate in the all-features job and verified gomplate --version
    • added a dedicated test-setup-gomplate job.

• Documentation

  • Updated README.md:
    • added setup-gomplate to inputs
    • included gomplate in feature summary
    • documented current Linux AMD64 artifact scope.

with:
  setup-gomplate: true

[Copilot]

Pull request overview

This PR adds optional gomplate setup support to the initialize-github-job composite action, including checksum-verified installation and CI coverage to validate the new feature.

Changes:

• Added a new setup-gomplate input (default false) and conditional gomplate install steps to action.yml.
• Implemented a checksum verification flow for downloading and installing gomplate v5.0.0 (Linux AMD64).
• Extended CI workflow coverage to exercise setup-gomplate and verify gomplate --version, plus added a dedicated gomplate job; updated README inputs/docs accordingly.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
action.yml	Adds setup-gomplate input and Linux AMD64 gomplate download + checksum verification + install steps.
README.md	Documents the new setup-gomplate input and notes current Linux AMD64 scope.
.github/workflows/test.yml	Enables gomplate in the all-features workflow and adds a dedicated job verifying installation.

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[Copilot]

The checksum lookup is grepping for bin/gomplate_linux-amd64, but the downloaded asset name is gomplate_linux-amd64. Unless the upstream checksums file actually includes the bin/ prefix, this will make EXPECTED_SHA empty and the step will always fail. Consider matching the exact asset filename present in the checksums file (and/or supporting both formats) to make the verification reliable.

Suggested change

	curl -sSfL "${GOMPLATE_RELEASE_URL}/gomplate_linux-amd64" \
	-o /tmp/gomplate || { echo "Failed to download gomplate binary"; exit 1; }
	curl -sSfL "${GOMPLATE_RELEASE_URL}/checksums-${GOMPLATE_VERSION}_sha256.txt" \
	-o /tmp/gomplate_checksums.txt || { echo "Failed to download gomplate checksums"; exit 1; }
	EXPECTED_SHA="$(grep 'bin/gomplate_linux-amd64$' /tmp/gomplate_checksums.txt | awk '{print $1}')"
	if [ -z "${EXPECTED_SHA}" ]; then
	echo "Unable to find checksum for gomplate_linux-amd64"
	GOMPLATE_ASSET="gomplate_linux-amd64"
	curl -sSfL "${GOMPLATE_RELEASE_URL}/${GOMPLATE_ASSET}" \
	-o /tmp/gomplate || { echo "Failed to download gomplate binary"; exit 1; }
	curl -sSfL "${GOMPLATE_RELEASE_URL}/checksums-${GOMPLATE_VERSION}_sha256.txt" \
	-o /tmp/gomplate_checksums.txt || { echo "Failed to download gomplate checksums"; exit 1; }
	EXPECTED_SHA="$(awk -v asset="${GOMPLATE_ASSET}" '$2 == asset || $2 == "bin/" asset { print $1; exit }' /tmp/gomplate_checksums.txt)"
	if [ -z "${EXPECTED_SHA}" ]; then
	echo "Unable to find checksum for ${GOMPLATE_ASSET}"

[Copilot]

This install path is Linux/AMD64-specific (gomplate_linux-amd64, sha256sum, /usr/local/bin, sudo). If a workflow runs this composite action on macOS/Windows or non-amd64 Linux with setup-gomplate: true, it will fail in a non-obvious way. Consider adding an explicit runner.os / architecture guard with a clear error message (or skipping) to match the documented scope.