feat(docker): add channel auto-enable and user auto-approval

Enable automatic channel configuration when bot tokens are provided via
environment variables. Previously channels were auto-detected but not enabled
due to --skip-channels flag.

Changes:
- Remove --skip-channels from onboarding to enable channel auto-configuration
- Add TELEGRAM_ALLOWED_USERS and DISCORD_ALLOWED_USERS environment variables
- Auto-configure channel allowlists when user IDs are provided
- Channels are now fully operational on first boot without manual pairing

This allows users to pre-approve specific Telegram/Discord user IDs,
skipping the pairing code step entirely. Users can message the bot
immediately after deployment.

docker-compose.phala.yml

@@ -21,6 +21,9 @@ services:
       # Channel tokens - auto-configures channels on first boot
       TELEGRAM_BOT_TOKEN: ${TELEGRAM_BOT_TOKEN:-}
       DISCORD_BOT_TOKEN: ${DISCORD_BOT_TOKEN:-}
+      # Pre-approved user IDs (optional, comma-separated)
+      TELEGRAM_ALLOWED_USERS: ${TELEGRAM_ALLOWED_USERS:-}
+      DISCORD_ALLOWED_USERS: ${DISCORD_ALLOWED_USERS:-}
       # Gateway configuration
       GATEWAY_PORT: ${GATEWAY_PORT:-18789}
       GATEWAY_AUTH: ${GATEWAY_AUTH:-off}