enhancement: Proactive LID handling hardening for June 2026 deadline

[wahyuwidgetworks]

Summary

Proactively harden LID (Linked ID) handling before WhatsApp's June 2026 Business API deadline when LID becomes mandatory.

Context

While investigating #2408, we confirmed that current LID handling works but has fragile assumptions:

What Works Today

• Real-time LID → phone resolution via remoteJidAlt (baileys:1589-1591)
• createConversation uses remoteJidAlt for LID contacts (chatwoot:635)
• Contact self-healing/merge when identifiers change (chatwoot:644-666)
• IsOnWhatsapp cache for historical sync (baileys:1623-1632)

Remaining Risks

1. No fallback if remoteJidAlt is missing — if remoteJidAlt is absent for a LID message, contact lookup fails or creates broken contact
2. Group participant LID — if participantAlt is missing for group messages, LID string is shown instead of phone number
3. Silent failures — LID resolution errors are not surfaced clearly in logs

Recommendations

1. Add defensive guards for missing remoteJidAlt
2. Improve logging for LID resolution (success/failure metrics)
3. Add fallback strategies (e.g., query IsOnWhatsapp table if remoteJidAlt missing)
4. Consider alerting when LID messages fail to resolve

WhatsApp LID Timeline

Milestone	Date	Impact
LID beta testing	Ongoing since Nov 2025	Increasing LID traffic
Username rollout	Early 2026	LID becomes default
Business API deadline	June 2026	All integrations must support LID

Priority

Medium — current implementation works, but LID volume will increase significantly through 2026.