Activity & Payment/Invoice view: How to round and display amounts/fees?

[myxmaster]

Describe your enhancement idea

Right now we are displaying amounts and fees in both views, Activity and Payment/Invoice details, by simply cutting off decimal places. We only use exact numbers (msat precision) in Payment Path view.

Activity:

My suggestion:
For Activity view:

• if something was rounded, make that clear by displaying "~" char (e.g. 1,235 sats + ~1 sat fee)
• use correct rounding (round up as of x.5, otherwise down)

For Payment/Invoice view:

• display exact numbers since we have more than enough real estate here
  -> in the end this is our "detailed" view and it should be precise, while the payment path view has a specific purpose but shouldn't be the only place where user can get exact numbers.

[myxmaster]

And: For any numbers denominated in fiat we can drop the "~" char, because everybody knows it is an approximation anyway.