Logging: add informative console logs for startup, ports, connections, JOIN/deny, input, and periodic events

- Configure logging via LOG_LEVEL env (default INFO)
- Log when servers start listening (WT/QUIC/InMemory/HTTPS static)
- Log WT CONNECT accept, QUIC peer connect, datagram traffic at DEBUG
- Log GameServer creation, tick loop start, JOIN accept/deny, config_update broadcasts, and input reception

server/server.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 import asyncio
 from dataclasses import dataclass
+import logging
 from typing import Dict, List, Optional, Tuple
 from collections import deque
 
@@ -53,6 +54,7 @@ class GameServer:
         self.runtime = ServerRuntime(config=config, state=GameState(config.width, config.height))
         self.sessions: Dict[int, PlayerSession] = {}
         self._config_update_interval_ticks = 50  # periodic resend
+        logging.info("GameServer created: field=%dx%d, tick_rate=%d TPS, wrap=%s", config.width, config.height, config.tick_rate, config.wrap_edges)
 
     async def on_datagram(self, data: bytes, peer: TransportPeer) -> None:
         # Minimal header parse
@@ -85,6 +87,7 @@ class GameServer:
         # Broadcast to all sessions (requires real peer handles)
         for session in list(self.sessions.values()):
             await self.transport.send(payload, TransportPeer(session.peer))
+        logging.debug("Broadcasted config_update to %d sessions", len(self.sessions))
 
     async def relay_input_broadcast(
         self,
@@ -115,6 +118,7 @@ class GameServer:
         r = self.runtime
         tick_duration = 1.0 / max(1, r.config.tick_rate)
         next_cfg_resend = self._config_update_interval_ticks
+        logging.info("Tick loop started at %.2f TPS", 1.0 / tick_duration)
         while True:
             start = asyncio.get_event_loop().time()
             # process inputs, update snakes, collisions, apples, deltas
@@ -388,12 +392,14 @@ class GameServer:
         if pid is None:
             payload = build_join_deny(version=self.runtime.version, seq=self.runtime.next_seq(), reason="Server full")
             await self.transport.send(payload, peer)
+            logging.warning("JOIN denied: server full (name=%s)", name)
             return
         # Spawn snake
         snake = self._find_spawn()
         if snake is None:
             payload = build_join_deny(version=self.runtime.version, seq=self.runtime.next_seq(), reason="No free cell, please wait")
             await self.transport.send(payload, peer)
+            logging.warning("JOIN denied: no free cell (name=%s)", name)
             return
         # Register session and snake
         color_id = preferred if (preferred is not None) else self._choose_color_id()
@@ -403,6 +409,7 @@ class GameServer:
         self.runtime.state.snakes[pid] = snake
         self.runtime.state.occupy_snake(snake)
         self._ensure_apples()
+        logging.info("JOIN accepted: player_id=%d name=%s color=%d len=%d at=%s", pid, name, color_id, snake.length, snake.body[0])
         # Send join_ack
         cfg = self.runtime.config
         ack = build_join_ack(
@@ -445,7 +452,7 @@ class GameServer:
             full = pack_header(
                 self.runtime.version, PacketType.STATE_FULL, 0, self.runtime.next_seq(), self.runtime.state.tick & 0xFFFF
             ) + body
-            await self.transport.send(full, peer)
+        await self.transport.send(full, peer)
         else:
             # Partition by packing whole snakes first, apples only in first part; chunk a single oversized snake using 2-bit chunks
             update_id = self.runtime.next_update_id()
@@ -563,6 +570,7 @@ class GameServer:
                 break
         if player_id is None:
             return
+        logging.debug("INPUT from player_id=%d: %d events (base_tick=%d)", player_id, len(events), base_tick)
         # Relay to others immediately for prediction
         await self.relay_input_broadcast(
             from_player_id=player_id,