Fix server clock reset in NetworkTimeSynchronizer and client-side peer 1 avatar duplicate

- Move _clock.set_time(0.) inside the 'if not server' block in
  NetworkTimeSynchronizer.start() so the server's SystemClock isn't
  reset to zero — fixes -1.78 billion second offset panic on client
- Skip spawning peer 1's avatar on clients (the server replicates
  all avatars; spawning peer 1 locally creates a duplicate that
  the dedicated server doesn't have)

addons/netfox/network-time-synchronizer.gd

@@ -142,10 +142,9 @@ signal on_panic(offset: float)
 func start() -> void:
 	if _active:
 		return
-		
-	_clock.set_time(0.)
 
 	if not multiplayer.is_server():
+		_clock.set_time(0.)
 		_active = true
 		_sample_idx = 0
 		_sample_buffer = _RingBuffer.new(sync_samples)