Add Docker image build and publish workflow

[Copilot]

Adds GitHub Actions workflow to automatically build and publish Docker images to GitHub Container Registry.

Workflow Configuration

• Triggers: pushes to main, version tags (v*), and PRs (build-only validation)
• Registry: GitHub Container Registry (ghcr.io)
• Tagging strategy:
  • Branch names for main builds
  • Semver patterns for release tags (v1.2.3 → 1.2.3, 1.2, 1)
  • Commit SHA with branch prefix for traceability

Implementation

• Builds static Go binary matching Makefile configuration (CGO_ENABLED=0, stripped, trimpath)
• Uses existing images/Dockerfile.prom2parquet
• Authenticates via GITHUB_TOKEN with scoped permissions (contents: read, packages: write)
• Conditional push: builds on PRs but only publishes on main/tags

Example Usage

After merging, images will be available at:

ghcr.io/walletconnect/prom2parquet:main          # latest main build
ghcr.io/walletconnect/prom2parquet:v1.2.3        # release version
ghcr.io/walletconnect/prom2parquet:main-abc1234  # specific commit

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• github.com (HTTP Only)
  • Triggering command: /usr/bin/ssh /usr/bin/ssh -o SendEnv=GIT_PROTOCOL git@github.com git-upload-pack 'acrlabs/build-scripts' (packet block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

make a workflow that builds and publishes the docker image

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[Copilot]

Pull request overview

This PR adds a GitHub Actions workflow to automatically build and publish Docker images to GitHub Container Registry (ghcr.io). The workflow is triggered on pushes to main, version tags, and pull requests (build-only for PRs).

• Builds a static Go binary matching the project's Makefile configuration
• Uses the existing images/Dockerfile.prom2parquet for containerization
• Implements a multi-tag strategy including branch names, semver patterns, and commit SHAs

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[Copilot]

The {{branch}} pattern variable is not valid in the docker/metadata-action. This will result in tags with literal {{branch}}- prefixes instead of the actual branch name. The metadata-action does not support dynamic prefix values in this way. Consider either using a static prefix like type=sha,prefix=sha- or removing the branch prefix entirely since the SHA itself provides unique identification.

Suggested change

	type=sha,prefix={{branch}}-
	type=sha,prefix=sha-