fix(chatwoot-adapter): stop a migrated @lid contact's inbound from splitting its conversation

[rmyndharis]

Summary

Stops a contact who has migrated to WhatsApp's @lid addressing from splitting into a duplicate Chatwoot conversation on the inbound path. This is the inbound mirror of the outbound fix shipped in 0.4.0 (#615).

Problem

resolveConversation looked up the mapping by the raw msg.chatId and created a new conversation on a miss. A contact whose conversation was mapped under <phone>@c.us (pre-migration) and has since migrated arrives with chatId = <lid>@lid, misses the @c.us mapping, and gets a second, duplicate conversation — the thread splits.

Fix

Reuse the host ctx.engine.canonicalChatId resolver (@lid → <phone>@c.us, best-effort) for a dual lookup: getByChat(raw) then getByChat(canonical). A migrated contact's inbound then lands in its existing @c.us conversation instead of a duplicate; a genuinely new chat still creates once.

Deliberate design points (arrived at via review):

• The per-chat lock stays keyed on the raw chatId, not the canonical id. canonicalChatId is best-effort and non-deterministic (it returns @c.us when the lid→phone cache is warm, @lid when cold, and needs a live engine), so keying the lock on it would let two inbound for the same chat lock different keys and double-create. The raw id is deterministic and already converges a migrated contact's inbound. Canonicalization is used only for the lookup.
• The lookup's canonicalChatId call is wrapped with a raw fallback, so it can never throw and drop a message before it is de-duplicated/queued (the retry drain re-relays messages whose WA session may be offline).
• refreshContactName now patches under the key the mapping actually lives under, so reusing a @c.us mapping via @lid records the synced name (no repeated updateContact on every later inbound).

Cold-store residual

canonicalChatId resolves only when the lid→phone mapping is known — after any outbound reply to the contact, or on every inbound when OpenWA's RESOLVE_LID_TO_PHONE=true is set (documented; it also helps the outbound path). A receive-only migrated contact on a default deployment can still create an @lid conversation until the store warms — same behavior as before the fix, now closable with that flag.

Compatibility

Version 0.5.1 (patch, bugfix). No core change (minOpenWAVersion stays 0.8.7). Non-@lid traffic (@c.us, groups) is byte-for-byte unchanged.