Channel notifications dropped after idle — messages lost between turns

Description

Using --channels plugin:telegram@claude-plugins-official with a Telegram group (forum/topics), inbound messages are frequently dropped even after the assistant has finished responding and the session appears idle (❯ prompt visible).

Steps to reproduce

1. Start Claude Code with --channels plugin:telegram@claude-plugins-official
2. Configure access.json with a group (supergroup with forum topics enabled)
3. Send a message from Telegram → Claude responds correctly
4. Wait for response to complete (idle ❯ prompt shown)
5. Send another message from Telegram
6. Message is silently dropped — no <channel> tag appears in session

Observed behavior

• First message after session start: delivered ✅
• Subsequent messages after a completed turn: ~70% dropped silently
• Sometimes 3-4 messages need to be sent before one gets through
• Adding a Stop hook that sends a status message to Telegram confirms the session is idle, but next message is still dropped
• No error in stderr, no 409 conflict — message simply never arrives

Expected behavior

All messages should be delivered to the session when it's idle, regardless of how many turns have completed.

Environment

• Claude Code: v2.1.92
• Plugin: telegram@claude-plugins-official v0.0.4
• Bot setup: grammy long polling, supergroup with forum topics
• OS: Linux (Ubuntu)

Related issues

#40604, #38259, #36477 — similar reports of channel messages being dropped after first response