Add Docker image publish workflow

[henmohr]

Summary

• add a GitHub Actions workflow to build and publish the Kimai PHP image to GHCR
• pass VERSION=2.6.0-prod to the Docker build
• add a Dockerfile default for VERSION so local builds do not resolve kimai/kimai2:fpm-

Validation

• docker build --progress=plain --build-arg VERSION=2.6.0-prod -f .docker/php/Dockerfile .docker/php
• git diff --check

Note: GitHub only allows workflow_dispatch for workflows present on the default branch, so this new workflow will publish after it is merged into main.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-15T16:59:13.650780Z	00b4fc7	PR opened

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[vitormattos]

Before we add a workflow to publish this image, I think we need to review why we still have a custom image.

Kimai already provides separate official images for production and development. kimai/kimai2:dev is specifically intended for local development, while the regular images are intended for production.

Our current Dockerfile seems to reproduce development concerns such as Xdebug, source code in a volume and a custom entrypoint. So instead of creating our own development and production tags, I think we should first check if we can replace this setup with the official Kimai images.

If the official dev image covers our development needs and the official production image covers production, we probably don't need this publish workflow or even this Dockerfile.

[henmohr]

Indeed. Maybe it's time to archieve this repo.

Current documentation of kimai is pretty good.

[vitormattos]

Could be.