Fix missing await in update_monitor_channels causing monitor channels to never update

[Claude]

The update_monitor_channels method was calling the async update_guild_channel without await, causing monitor channels to never update and generating RuntimeWarning: coroutine was never awaited in Python 3.10+.

Changes

• Added missing await keyword in update_monitor_channels loop (line 134)

Before

async def update_monitor_channels(self):
    for guild in self.bot.guilds:
        self.update_guild_channel(guild)  # ❌ Missing await

After

async def update_monitor_channels(self):
    for guild in self.bot.guilds:
        await self.update_guild_channel(guild)  # ✅ Fixed

This restores the monitor channel feature, which updates voice channel names with server status every 5 minutes via the background task loop.