Two Hermes bots sharing a channel could volley replies at each other
indefinitely. Root cause: Discord reply-pings (allowed_mentions
replied_user=true) add the replied-to bot to message.mentions without a
literal <@bot> token in the body, so the existing bot-admission gate
treated a reply chip as an explicit @mention and re-triggered the peer.
Adds opt-in discord.bots_require_inline_mention (default false; env
DISCORD_BOTS_REQUIRE_INLINE_MENTION). When enabled, bot-authored
messages must carry a raw inline <@id>/<@!id> mention in the content;
reply-ping-only mentions no longer admit the message. Human messages and
all existing defaults are unchanged.
The new _self_is_raw_mentioned helper deliberately ignores the resolved
message.mentions list (which reply-ping populates) and checks only the
raw content token via the shared _raw_mentioned_user_ids primitive.