Fix MAP12/MAP3E HA discovery after WB 2606 MQTT convention change

[thebestbaduser]

Summary

• Add MAP device aliases (map12e, wb-map12e, wb-map12e-fw2, wb-map12h, wb-map3et, wb-map3ev) so wb-map3e control rules apply to MAP12 and updated MAP3 templates
• Add regex patterns for MAP12 channel names (Urms L1, Ch N Irms L1, Ch N Total AP energy, etc.)
• Round voltage values in HA MQTT discovery (value_template for voltage type)
• Read units from MQTT control meta (WB 2606 conventions)

Problem

After updating Wiren Board to wb-2606, MAP meters stopped publishing correct Home Assistant MQTT discovery payloads.

wb-mqtt-serial changed MAP templates from deprecated control types (voltage, current, ...) to universal type: value with separate units metadata (see wb-2606 changelog).

wb-engine then published bare sensors like:

{
  "default_entity_id": "value_state.wb-map12e_244_urms_l1",
  "state_topic": "/devices/wb-map12e_244/controls/Urms L1"
}

Without device_class, unit_of_measurement, or state_class, Home Assistant treated values as plain text states — no graphs, no kWh counters.

Test plan

• Verified on WB-MAP12E fw2 (wb-map12e_244) after wb-2606 update
• Urms L1 publishes with device_class: voltage, unit_of_measurement: V, line graphs restored
• Ch N Total AP energy publishes with device_class: energy, unit_of_measurement: kWh, state_class: total_increasing
• Maintainer review of regex coverage for other MAP12 channel names