Use DataPoints for all PowerMeter Providers

[AndreasBoehm]

With this PR we switch all PowerMeter Providers to use DataPoints. This will allow us to easily build a HASS integration, show individual phase values in the LiveView and also to group inverters by phase within the DPL.

Additonaly i added reading the total power directly for 3-phase SDM powermeters as requested in issue #765

Tested Providers

• HTTP
• MQTT
• SDM 1-Phase
• SDM 3-Phase
• SML via Serial
• SML via HTTP
• SMA HomeManager2

Test version

https://github.com/hoylabs/OpenDTU-OnBattery/actions/runs/13398033363

[schlimmchen]

Man, this is awesome ❤️ As the power meters basically all provide the same stuff, we finally have a common baseline for all of them. There is one catch: If one providers delivers values that are unique to it, there has to be a data label for it even though only it uses the value. I think that should be fine.

I also renamed 'Values' to 'Phases' int the web ui to make this change kind of visible.

That I actually don't like... For one that we are mixing concerns/features/changes. More importantly, I changed the name from "phases" to "values" for a reason: They are only values, the readings are not always associated with phases. Example: We had the guy who has a power meter which delivers a power value in one JSON path when importing energy, and in another path when exporting energy. We told him to configure two values, one for each JSON path/value, with the one inverted.

Why do you think the usability improves when the wording is "phases"?

[AndreasBoehm]

It felt better for me to setup phases instead of values. Thinking about it, the only real usecase is that if we want to show L1, L2, L3 power in the liveview with exactly those labels it will match with the configuration view, but besides that there is actually no need to call it phases.

Let me take back that change.

[AndreasBoehm]

Values are back 🔙