Add 👀 emoji acknowledgment for incoming messages

[alexknowshtml]

Summary

When a new message comes in and the bot is already processing, react with 👀 to acknowledge receipt.

How Andy's System Does It

In discord-agent-bridge, the acknowledgment is server-side driven:

1. Discord bot receives message, sends it to session manager via webhook
2. Session manager returns { busy: true } if already processing
3. Bot reacts with 👀 when it receives busy: true

The system also uses:

• ⏸️ for paused threads
• ▶️ for resumed threads
• 👀 for busy (message received, will process when ready)

Decision: Option B (Server-side)

Chosen approach: Check BullMQ queue depth, only show 👀 if jobs are already queued for this thread.

Implementation

1. Message received → Queue job
2. Before queueing, check if thread already has waiting/active jobs in BullMQ
3. If queue has pending jobs → React with 👀
4. If queue is empty → No reaction (response will come quickly)

Why This Over Option A

• More accurate - doesn't show 👀 for instant responses
• Matches Andy's existing behavior
• Better UX - 👀 means "I see you, working on something else first"

Reference

See system/repos/discord-agent-bridge/src/bot.ts lines 360-363