docker: publish branch-aligned repeater images and trigger rebuilds from core

[yellowcooln]

PR Summary

This PR fixes how pyMC_Repeater Docker images are built and consumed so published images reliably track the matching pyMC_core branch and commit state.

Before this change, Docker builds installed repeater using a plain:

pip install .

That allowed the pyMC_core@dev dependency to remain stale inside freshly published images if Docker reused cached layers.

The sample docker-compose.yml also rebuilt locally instead of pulling the published image, which bypassed the Docker publish workflow entirely.

This PR makes the Docker pipeline deterministic and channel-aware.

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What Changed

Deterministic pyMC_core Pinning

Docker builds are now branch-aware:

• dev repeater images build against pyMC_core@dev
• main repeater images build against pyMC_core@main

The publish workflow now:

• Resolves the exact current pyMC_core commit SHA at build time

• Passes both:

  • PYMC_CORE_REF
  • PYMC_CORE_SHA

• Installs pyMC_core by exact commit SHA

• Installs repeater using:

  • pip install --no-deps

This guarantees the published image contains a pinned and traceable pyMC_core revision instead of a floating or cached branch tip.

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Docker Consumption Changes

The sample container workflow now consumes published images directly instead of rebuilding locally.

docker-compose.yml

Updated to:

• Use image: instead of build:

• Set:

  • pull_policy: always

• Pass:

  • PUID
  • PGID

as runtime environment variables instead of build args.

README Updates

Documentation now instructs users to:

docker compose pull
docker compose up -d --force-recreate

This ensures deployments actually receive the latest published image.

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CI / Workflow Changes

Repeater Docker Publish Workflow

Extended .github/workflows/docker-publish.yml to support automatic rebuilds when pyMC_core changes.

Added:

• repository_dispatch support

• Dispatch payload support for:

  • channel
  • core_ref
  • core_sha

• Matching repeater branch checkout for dispatch-triggered rebuilds

• Docker tagging by:

  • Channel
  • Repeater SHA

• OCI-style image labels for:

  • Repeater revision
  • Core ref
  • Core SHA

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pyMC_core Trigger Workflow

Added companion workflow:

• .github/workflows/trigger-repeater-docker-rebuild.yml

This workflow:

• Triggers on main and dev pushes

• Dispatches rebuild events to the repeater repo

• Sends:

  • Matching channel
  • Exact core commit SHA

This allows a new pyMC_core merge to automatically rebuild the correct repeater Docker image.

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Files Changed

Repeater

• dockerfile
• .github/workflows/docker-publish.yml
• docker-compose.yml
• README.md

Core

• .github/workflows/trigger-repeater-docker-rebuild.yml

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Why This Matters

This removes the stale-core-in-fresh-image problem and keeps main and dev channels aligned across repositories.

It also makes the published Docker images the real source of truth for:

• Direct Docker users
• Downstream consumers
• Home Assistant add-ons
• Automated deployments

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Notes

Required Secret

The core-side dispatch workflow requires:

• REPEATER_REPO_DISPATCH_TOKEN

Manual Workflow Support

The repeater publish workflow still supports manual workflow_dispatch, but:

• Normal channel selection is now automatic
• Manual core commit entry is no longer required