Add bluetooth support for Amphiro / Oras digital shower head

**Describe the problem you have/What new integration you would like**

Bluetooth tracking of Oras amphiro digital hand shower use and energy
Product page: https://www.amphiro.com/en/products/digital-hand-shower

**Please describe your use case for this integration and alternatives you've tried:**

Add support to track measuring for Amphiro / Oras digital shower head via bluetooth
There is already a few working variants eg. OMG supports it but native support for esphome would be nice.

All necessary details can be found in https://github.com/1technophile/OpenMQTTGateway/issues/1263
OMG is using Theengs decoder
https://github.com/theengs/decoder/commit/f26a0faefb905265453ac8fae797f956b48eacd8
https://github.com/theengs/decoder/blob/development/src/devices/Amphiro_json.h

Protocol has also been reverse-engineered in here. https://gitlab.com/baze/amphiro_oras_bluetooth_shower_hub/-/tree/main/Protocol_description

**Additional context**

Start with the linked OpenMQTTGateway issue and theengs/decoder's src/devices/Amphiro_json.h, then read the Protocol_description material in the linked repository. Determine the appropriate ESPHome Bluetooth integration entry point and define completion as native support that tracks Amphiro/Oras shower use and energy measurements.

Written by the indexing model from the issue text.