Add failed contracts to the graph

[npelov]

Description

It would be nice to see the failed contracts in the Revenue graph and maybe loss due offline time. I know that if everythign is right the fails are very rare, but I have a host that fails a lot (maybe something is wrong with the database, storage is fine). When this happens you will want to know what you are loosing and maybe stop accepting contracts, then rebuild the node.

Version

v2.1

What operating system are you running (e.g. Ubuntu 22.04, macOS, Windows 11)?

docker on debian 12

Anything else?

I'm not sure how you can see the loss in the graph. Not sure if going below 0 will look good.. for the loos due offline it can be different color (darker red, orange maybe) on top of the gain. For failed contracts - not sure.