Add DISCORD_ALLOWED_CHANNELS (env var) / discord.allowed_channels (config.yaml)
support to restrict the bot to only respond in specified channels.
When set, messages from any channel NOT in the allowed list are silently
ignored — even if the bot is @mentioned. This provides a secure default-
deny posture vs the existing ignored_channels which is default-allow.
This is especially useful when bots in other channels may create new
channels dynamically (e.g., project bots) — a blacklist requires constant
maintenance while a whitelist is set-and-forget.
Follows the same config pattern as ignored_channels and free_response_channels:
- Env var: DISCORD_ALLOWED_CHANNELS (comma-separated channel IDs)
- Config: discord.allowed_channels (string or list of channel IDs)
- Env var takes precedence over config.yaml
- Empty/unset = no restriction (backward compatible)
Files changed:
- gateway/platforms/discord.py: check allowed_channels before ignored_channels
- gateway/config.py: map discord.allowed_channels → DISCORD_ALLOWED_CHANNELS
- hermes_cli/config.py: add allowed_channels to DEFAULT_CONFIG