Add friendly_name for sensors and other entities

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

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

**Additional context**

I have purposely defined names for all my sensors/entities in the YAML code. I had a good reason for that, but since 2025.4, all my entities were renamed in the HA frontend. Now my front-end is unusable because the device names take all the visible space. The only proposed solution is to fix this manually in the UI which, needless to say, is a lot of unnecessary work.

Beeing "name" an optional attribute, the expected behaviour would be that this optional "name" is kept through all the HA experience. As I know this goes against the HA convention, my proposal is to add the possibility to define the name of the sensors/entities in YAML. I will give an example of why this convention is a bad idea for ESPHOME:

- I have 2 rooms that are really close, with bluetooth temperature sensors. As the sensors are really close, I can read the values of both with a single ESP32
- I placed an ESP32 in one of the rooms. Now I have to name this ESP32, and I put the location of this ESP32 as it's name. This ESP32 is named "esp-room-1"
- Room 1 temperature sensor has name "Room 1 temperature"
- Room 2 temperature sensor has name "Room 2 temperature"
- Now in frontend I see "ESP Room 1 Room ..." and "ESP Room 1 Room ..."

My request is that any entity in HA should be able to get an optional "friendly_name" in such a way that the user can define in YAML what is the desired name for this particular entity. This way, we could just change our optional "name" by "friendly_name" in all our YAML files and recover the good old behaviour.

Thank you!

No files, tests, or entry points are identified in the request. Start by tracing how YAML entity names are represented and displayed in the Home Assistant frontend, then define how an optional friendly_name should override device-derived names without breaking existing naming conventions.

Written by the indexing model from the issue text.