Initial draft for helm chart

[jlpedrosa]

This PR follows up on #21823, it contains the main skeleton to open the conversation. If merged the following items (at least needs to be addressed):

• Documentation is created in the doc repo in this PR.

This chart uses a config map to store the configuration, and extracts groups and devices to external files, so it can be managed by the UI. The downside of this approach is that all the other setting are not writable through the UI and needs to be managed through the helm chart.

I've tested this helm chart with:

• no storage (emptyDir)
• dynamically provisioned volumes
• statically provisioned volumes.

[Koenkk]

If merged the following items (at least needs to be addressed):

Can we address it in this PR?

[jlpedrosa]

If merged the following items (at least needs to be addressed):

Can we address it in this PR?

No problem, I was thinking you may want to split the PR into more smaller chunks, I will update the PR with the docs and the CI

[jlpedrosa]

@Koenkk I can't add you to reviewers, from my perspective is ready for review.

[Koenkk]

Thanks for all your updates, added 2 more comments, after those are solved this can be merged 🥳

Note to self; after this merge https://github.com/Koenkk/zigbee2mqtt.io/pull/2738

[Koenkk]

Many thanks for all the effort that went into this! 😄