Config UI: EEBus activation

[naltatis]

Allow user to generate and persist EEBus certs (see evcc eebus) via UI.

[andig]

Either that or auto-generate certa but allow overriding? From file only instead of string???

[naltatis]

I'd say auto-gen on activate through user. Not sure if we really need a manual upload or cert entry. Can still be done via CLI really necessary.

[andig]

Still need to maintain current setups?

[naltatis]

Yes, I'd say we can migrate yaml based configurations. Only auto-gen if user wants to activate and no certain is found in config.

[CiNcH83]

I would also like to link this issue in the docs:

I switched from machine-id to plant ID. I could easily migrate the EEBUS YAML configuration (plant ID+certs) to another machine. evcc came up with the same SHIPID and all associations have been intact. Especially with regards to the FNN controlbox this will spare you a roundtrip with the grid operator who has to approve the changed SKI. Of course copying the configuration can also be dangerous. If you don't know what do you, you will have multiple devices with the same SHIPID in the network...