fix: remove privileged intents not needed for radio plugin

Only request Guilds + GuildVoiceStates. GuildMembers, GuildPresences
and MessageContent are privileged and require manual portal activation.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/core/discord.ts

@@ -4,10 +4,6 @@ const client = new Client({
   intents: [
     GatewayIntentBits.Guilds,
     GatewayIntentBits.GuildVoiceStates,
-    GatewayIntentBits.GuildMembers,
-    GatewayIntentBits.GuildMessages,
-    GatewayIntentBits.GuildPresences,
-    GatewayIntentBits.MessageContent,
   ],
 });