Feature Request

Problem

Currently Hermes only discovers forum threads in two ways:

1. DM topics — created at startup via dm_topics config (createForumTopic)
2. Incoming messages — message_thread_id is captured from messages arriving in existing threads

If a user manually creates a new topic in a group (or another admin bot creates one), Hermes has no way to discover it. The Bot API has no getForumTopics method (open request: tdlib/telegram-bot-api#634), so there is no way to query the list of existing topics.

Proposed Solution

Handle the forum_topic_created update from Telegram and surface it to the agent.

When a new topic is created in a chat where Hermes is a member/admin:

1. Gateway receives the forum_topic_created update
2. Gateway notifies the agent with the details: chat_id, message_thread_id, name, icon_custom_emoji_id
3. Agent can then update memory/config to register the new thread for future message routing

Implementation Notes

• The forum_topic_created field is already present in Telegram Message objects when a topic is created
• This should fire alongside the normal message pipeline — the Message update that carries forum_topic_created can be augmented with metadata
• Optional: also handle forum_topic_edited (renamed) and forum_topic_closed/forum_topic_reopened for full lifecycle tracking

Use Case

User creates a new topic like "Deployments" or "Incident Response" in a Hermes-enabled group. Instead of manually sharing the thread ID with Hermes, the bot auto-discovers it and can route messages there.

Related Issues

• [Bug]: Telegram DM sends fail with 'Message thread not found' — spurious thread_id from reply chains #3206 — Thread ID handling bugs in non-forum DMs
• Feature: Telegram Private Chat Topics support for project-based conversations #2598 — Private chat topics support (implemented)
• tdlib/telegram-bot-api#634 — Bot API lacks getForumTopics method