Migrate `op-deployer` Docker build to GitHub Actions

[falcorocks]

Migrate op-deployer Docker build to GitHub Actions

Summary

op-deployer is the last remaining Docker image still built on CircleCI. All other images were migrated to GitHub Actions in #18821. The op-deployer image was excluded because its build depends on pre-compiled Solidity contract artifacts passed via CircleCI workspace attachment, rather than being built atomically inside Docker.

A prior attempt to make the Docker build self-contained was made in #19088 but was reverted in #19106 due to performance issues on CircleCI runners.

Goal

Complete the migration of op-deployer to GitHub Actions and clean up the now-unnecessary CircleCI docker build infrastructure.

Current State

• The op-deployer Docker build relies on a contracts-bedrock-build CircleCI job that compiles Solidity contracts and copies artifacts into op-deployer/pkg/deployer/artifacts/forge-artifacts via workspace attachment.
• The docker-build CircleCI job then uses those pre-built artifacts via attach_workspace to build the image.
• The Dockerfile op-deployer-builder stage and op-deployer-target stage assume the artifacts are already present in the build context.
• All other images are built in GitHub Actions via branches.yaml and tags.yaml using docker-bake.hcl.

Tasks

1. Recover and adapt the atomic Docker build for op-deployer

Recover the work from #19088 that made op-deployer build its contract artifacts inside the Docker build itself (i.e., no external workspace attachment needed). The revert in #19106 was due to CircleCI runner constraints, which are no longer relevant since the build will run on GitHub Actions runners.

2. Verify feature parity

Ensure the atomically-built op-deployer image is functionally equivalent to the existing CircleCI-built image:

• Embedded contract artifacts must match.
• The forge binary must be present and at the correct version.
• The op-deployer binary must behave identically.
• Run the existing op-deployer test script against the new image.

3. Add op-deployer to GitHub Actions build matrix

Add op-deployer to the image matrix in branches.yaml and tags.yaml. The docker-bake.hcl target already exists.

4. Remove op-deployer from CircleCI docker builds

Remove the op-deployer entry from the CircleCI docker-build matrix in the main workflow, as well as any release/scheduled workflow entries that build the op-deployer Docker image.

5. Clean up deprecated CircleCI docker build infrastructure

Once op-deployer is removed, the docker-build job in CircleCI has no remaining consumers. Clean up:

• The docker-build job definition and its associated steps.
• Any workflow references to docker-build.
• Any CircleCI-only docker build utilities or scripts that are no longer referenced.

Preserve the contracts-bedrock-build job

Acceptance Criteria

• op-deployer Docker image builds successfully in GitHub Actions without any external artifact preparation step.
• The new image passes all existing tests and matches the behavior of the CircleCI-built image.
• op-deployer appears in the GitHub Actions build matrix for both branch and tag workflows.
• CircleCI no longer builds any Docker images.
• No orphaned CircleCI job definitions related to docker-build remain.
• Builds continue to use the reusable factory docker workflow.