Make `ProtocolWarnings 1` less noisy to run
While investigating the right fix for #40175 (closed), Sebastian reminded me that we get lots of frequent protocol warnings. We should make these less frequent so that it's less of a burden to run Tor with protocol warnings enabled.
The most common warnings that Sebastian encountered are:
84853 Rejecting RENDEZVOUS1 cell with unrecognized rendezvous cookie 9975 Didn't recognize cell, but circ stops here 10002 circuit_receive_relay_cell (forward) failed
- Downgrade to INFO or DEBUG.
- Add rate-limiting
- Identify cases that truly should be protocol warnings, and downgrade or rate-limit the other cases.