[Feature Request] Show fees in per Byte format

[HardenedSteel]

It would be great to have showing fees in per byte format like Nanoneros/Byte

[azalty]

+set the ability to modify the fee, as a check in the settings to propose this, or in the advanced transaction details

Because as we are currently seeing, the auto transaction fee isn't working properly.

[chaserene]

if this is approved, please also show the fee rate in the transaction details (right-click on a transaction -> Show details) in a new line. I'd argue that, in most cases, it's even more important than the absolute fee value, so it could come before the Fee line.

this would also give a basis for the expected confirmation time for the receiver, since receivers currently don't see the absolute fee value, only that it was Paid by sender.