WhatsApp recently changed to send self-chat messages using LID (Linked
ID) format (e.g., xxxxxx@lid) instead of phone number format (e.g.,
xxxxxx@s.whatsapp.net). This caused messages to yourself to be silently
dropped because they didn't match any registered group.
## How to reproduce
1. Send a message to yourself on WhatsApp with the trigger
2. Message is received by Baileys but remoteJid is in LID format
3. LID JID doesn't match registered group JID (phone format)
4. Message is not stored and no response is sent
## The fix
- Build a LID-to-phone mapping from sock.user on connection open
- Translate incoming LID JIDs to phone JIDs before storing/processing messages
- This allows self-chat messages to correctly match the registered main channel
The mapping is populated from sock.user.id (phone) and sock.user.lid (LID)
which Baileys provides after successful authentication.
