Add tests for MQTT and Operations

[Prior99]

This PR adds tests for MQTT and all operations.

This also fixes some issues along the lines:

• We forgot to expose set_charge_mode as an operation
• We didn't wait until a topic was actually subscribed to
• Some aliases in the events from MQTT were wrong
• We didn't wait until the client is actually disconnected in mqtt.disconnect
• When using honk_and_flash with only flash, the wrong MQTT operation was awaited

And improves some other things:

• Events are now dataclasses
• CLI code is no longer taken into account for coverage report

[WebSpider]

LGTM!
Minor remark: Maybe we limit python to the version that HA supports as we ship the release. Right now this is 3.12 only.