Bug Description

Telegram channel posts containing slash commands were not reaching the command handler, so commands like /sethome failed when posted from channels.

Root Cause

The Telegram adapter only registered the normal command handler, and _handle_command() only read update.message. Telegram channel-post commands arrive via update.channel_post / update.edited_channel_post, so they were ignored.

Fix

• register a Telegram command handler for filters.UpdateType.CHANNEL_POSTS & filters.COMMAND
• normalize command updates through a small helper that accepts message, edited_message, channel_post, and edited_channel_post
• add regression tests covering both channel-post command routing and handler registration

How to Verify

1. source venv/bin/activate && python -m pytest tests/gateway/test_telegram_channel_posts.py tests/gateway/test_telegram_group_gating.py tests/gateway/test_telegram_reactions.py -q
2. Post a slash command like /sethome in a Telegram channel where Hermes is admin
3. Confirm the command reaches the gateway command handler instead of being ignored

Test Plan

• Added regression test for this bug
• Existing targeted Telegram tests still pass
• Manual verification in a live Telegram channel

Risk Assessment

Low — the change is narrowly scoped to Telegram command update routing and is covered by targeted regression tests.