fix: use pub_key() instead of peer() in connect tracing

The acceptor's PeerAddr is intentionally Unknown (NAT scenario) since
the local peer doesn't know its external address yet. Use pub_key()
instead of peer() to avoid panics on unknown addresses.

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Co-Authored-By: Claude <[email protected]>

Author: sanity

crates/core/src/operations/connect.rs

@@ -320,8 +320,8 @@ impl RelayState {
             // Use the joiner with updated observed address for response routing
             actions.response_target = Some(self.request.joiner.clone());
             tracing::info!(
-                acceptor_peer = %acceptor.peer(),
-                joiner_peer = %self.request.joiner.peer(),
+                acceptor_pub_key = %acceptor.pub_key(),
+                joiner_pub_key = %self.request.joiner.pub_key(),
                 acceptor_loc = ?acceptor.location,
                 joiner_loc = ?self.request.joiner.location,
                 ring_distance = ?dist,