ADD: Fee Recipient via API

[NeoPlays]

waiting for implementation on client side

• Lighthouse
• Prysm
• Nimbus
• Teku

[MaxTheGeeek]

@NeoPlays which part of the fee recipient r u working on?

[NeoPlays]

@NeoPlays which part of the fee recipient r u working on?

functionality of this thing but the teku client hasn't implemented it yet.. actually it's done already 😅

[NeoPlays]

i took out the frontend implementation to avoid future conflicts.
I tested the import on:

• Teku - Response: ""
• Lighthouse - Response: null
• Nimbus - Response: ""
• Prysm - Response: ""

The imports where successful for all clients where i was able to check the fee recipient in a file.
I couldn't find any file for prysm but the api request didn't fail either.
I also tested restarting the containers to check if the --validators-proposer-default-fee-recipient would overright the api import and they don't, so the api has higher priority just like some docs state.

[stefa2k]

lgtm, but somebody with JS experience should look over it too

[mabasian]

lg