Fix multi platform build and add docs

[maslyankov]

PR Description:

Fixes and Enhancements:

• Resolved issues with image tagging across different platforms.
• Streamlined the tagging process to support all platforms while maintaining backwards compatibility.

Documentation Update:

• Added comprehensive documentation for standalone deployment of the hass-addon-sunsynk-multi service using Docker Compose and Docker CLI.
• Provided detailed examples for local Docker builds and pre-built images for various architectures (amd64, aarch64, armv7).
• Documented instructions for running the addon alongside mbusd on Raspberry Pi and other hosts without requiring Home Assistant.

Cleanups:

• Removed unnecessary steps and streamlined the instructions for easier deployment.

This PR ensures smoother multi-platform support and provides clarity for users setting up the addon in standalone environments.

Example packages: https://github.com/maslyankov?tab=packages&repo_name=sunsynk Example run: https://github.com/maslyankov/sunsynk/actions/runs/11375051809 Docs: https://github.com/maslyankov/sunsynk/blob/improvement/finish-up-multibase-build-workflow/www/docs/guide/standalone-deployment.md

[maslyankov]

@kellerza Any thoughts on this?

[kellerza]

Thanks @maslyankov

I started a first manual run as a test - https://github.com/kellerza/sunsynk/actions/runs/11541954309

Once everything is ok, we probably need the dev version trigger. And then we can comment out the triggers in the old build process

  workflow_run:
    workflows: ["CI"]
    branches: [main]
    types:
      - completed

[kellerza]

Seems the merge step failed

[maslyankov]

Seems the merge step failed

I will look into it. Can you try to rerun it just in case?