labgrid/driver/power: Add Tapo(Kasa) smart plug support

[onurcelep]

Description
Adds power driver integration for Tapo Smart plugs with Klap authentication.
python-kasa requires KASA_USERNAME and KASA_PASSWORD environment variables to be set to handle the authentication.

Checklist

• Documentation for the feature
• Tests for the feature

• The arguments and description in doc/configuration.rst have been updated

• Add a section on how to use the feature to doc/usage.rst

• Add a section on how to use the feature to doc/development.rst

• PR has been tested

• Man pages have been regenerated

[Emantor]

The tp-link power driver also uses the kasa plugin, but seems to be much simpler since it employs the SmartStrip abstraction. Is there something similar inside kasa for smart plugs?

[onurcelep]

Apparently available class for Tapo smart plugs is smart.SmartDevice , tried to find similar abstraction as SmartStrip but unfortunately not available 🫤
Introducing KlapTransportV2 auth type of transport particularly brings the complexity here. I just fetched that information from debugging while using python-kasa on my local to power on/off devices

[onurcelep]

Closing in favor of #1630 which provides a more complete implementation kasa API version compatibility (< 0.10.0 and >= 0.10.0), power strip support via device.children, proper unit tests, and type annotations.