Usync: Barebones Usync Protocol support (#960)

* feature(feature/usync-mex): initial commit

* chore: fix merge commit

* chore:lint

src/WAUSync/Protocols/USyncContactProtocol.ts

@@ -0,0 +1,32 @@
+import { USyncQueryProtocol } from '../../Types/USync'
+import { assertNodeErrorFree, BinaryNode } from '../../WABinary'
+import { USyncUser } from '../USyncUser'
+
+export class USyncContactProtocol implements USyncQueryProtocol {
+	name = 'contact'
+
+	getQueryElement(): BinaryNode {
+		return {
+			tag: 'contact',
+			attrs: {},
+		}
+	}
+
+	getUserElement(user: USyncUser): BinaryNode {
+		//TODO: Implement type / username fields (not yet supported)
+		return {
+			tag: 'contact',
+			attrs: {},
+			content: user.phone,
+		}
+	}
+
+	parser(node: BinaryNode): boolean {
+		if(node.tag === 'contact') {
+			assertNodeErrorFree(node)
+			return node?.attrs?.type === 'in'
+		}
+
+		return false
+	}
+}