feat: add inbound username support and USync username protocol (#382)

* feat: add inbound username support and USync username protocol

Aligns with Baileys upstream PR #2480. WhatsApp is rolling out an
inbound username field that maps to the user's LID. This change is
purely additive — it captures and propagates the new optional field
through types, decoders, USync queries, and group/contact events.

Skipped intentionally to preserve InfiniteAPI's LID/PN customization:
- handleGroupNotification in messages-recv.ts (custom LID->PN flow on
  groups.upsert / participants.map). Username for these specific
  events still flows via process-message's emitParticipantsUpdate
  (reads message.key.participantUsername added in decode-wa-message).

Carousel/buttons code (messages.ts, messages-send.ts) untouched.

Co-Authored-By: Renato Alcara

src/Socket/groups.ts

@@ -343,11 +343,13 @@ export const extractGroupMetadata = (result: BinaryNode) => {
 	let descId: string | undefined
 	let descOwner: string | undefined
 	let descOwnerPn: string | undefined
+	let descOwnerUsername: string | undefined
 	let descTime: number | undefined
 	if (descChild) {
 		desc = getBinaryNodeChildString(descChild, 'body')
 		descOwner = descChild.attrs.participant ? jidNormalizedUser(descChild.attrs.participant) : undefined
 		descOwnerPn = descChild.attrs.participant_pn ? jidNormalizedUser(descChild.attrs.participant_pn) : undefined
+		descOwnerUsername = descChild.attrs.participant_username || undefined
 		descTime = +descChild.attrs.t!
 		descId = descChild.attrs.id
 	}
@@ -362,16 +364,19 @@ export const extractGroupMetadata = (result: BinaryNode) => {
 		subject: group.attrs.subject!,
 		subjectOwner: group.attrs.s_o,
 		subjectOwnerPn: group.attrs.s_o_pn,
+		subjectOwnerUsername: group.attrs.s_o_username,
 		subjectTime: +(group.attrs.s_t ?? '0'),
 		size: group.attrs.size ? +group.attrs.size : getBinaryNodeChildren(group, 'participant').length,
 		creation: +(group.attrs.creation ?? '0'),
 		owner: group.attrs.creator ? jidNormalizedUser(group.attrs.creator) : undefined,
 		ownerPn: group.attrs.creator_pn ? jidNormalizedUser(group.attrs.creator_pn) : undefined,
+		ownerUsername: group.attrs.creator_username || undefined,
 		owner_country_code: group.attrs.creator_country_code,
 		desc,
 		descId,
 		descOwner,
 		descOwnerPn,
+		descOwnerUsername,
 		descTime,
 		linkedParent: getBinaryNodeChild(group, 'linked_parent')?.attrs.jid || undefined,
 		restrict: !!getBinaryNodeChild(group, 'locked'),
@@ -386,6 +391,7 @@ export const extractGroupMetadata = (result: BinaryNode) => {
 				id: attrs.jid!,
 				phoneNumber: isLidUser(attrs.jid) && isPnUser(attrs.phone_number) ? attrs.phone_number : undefined,
 				lid: isPnUser(attrs.jid) && isLidUser(attrs.lid) ? attrs.lid : undefined,
+				username: attrs.participant_username || attrs.username || undefined,
 				admin: (attrs.type || null) as GroupParticipant['admin']
 			}
 		}),

src/Socket/messages-recv.ts

@@ -2223,6 +2223,7 @@ export const makeMessagesRecvSocket = (config: SocketConfig) => {
 							fromMe,
 							participant: node.attrs.participant,
 							participantAlt,
+							participantUsername: node.attrs.participant_username,
 							addressingMode,
 							id: node.attrs.id,
 							...(msg.key || {})
@@ -2231,6 +2232,10 @@ export const makeMessagesRecvSocket = (config: SocketConfig) => {
 						msg.messageTimestamp = +node.attrs.t!
 
 						const fullMsg = proto.WebMessageInfo.fromObject(msg) as WAMessage
+						// Preserve custom WAMessageKey fields (participantAlt, participantUsername,
+						// addressingMode) that proto.WebMessageInfo.fromObject strips because
+						// they aren't part of the proto.MessageKey schema.
+						fullMsg.key = msg.key
 						await upsertMessage(fullMsg, 'append')
 					}
 				})