socks: Add a new extended error to indicate when client is unable to solve the PoW

We can use X'F8' for this one that would indicate that solving the PoW for a specific onion connection failed.

changed milestone to %Tor: 0.4.8.x-stable

added Onion Services Onion Services Coalition labels

Hmmm so it appears that if the client fails to solve the effort, it just retries... so it seems we can not endup in a situation where the client can just "fail".

Seems it will rather simply timeout with the SocksTimeout which means at that point, we should reply with that extended error indicating that "we tried but couldn't solve".

added Backlog label

changed milestone to %Tor: 0.4.8.x-post-stable

Lets still get this in 048 post stable especially before first TB stable with 048.

Hmmm so this is out of scope now... We'll ask arti to do this but C-tor client won't see this feature due to the deprecation path it is on.

added Close in favor of Arti label

closed