🔊 log error on URL routing failures

crates/ptth_relay/src/routing.rs

@@ -125,6 +125,7 @@ pub fn route_url <'a> (method: &Method, path: &'a str) -> Result <Route <'a>, Er
 		})
 	}
 	else {
+		tracing::error! ("URL routing failed for `{}`", path);
 		Err (Error::NotFound)
 	}
 }