chore: add type distinguisher for sockets

src/LegacySocket/socket.ts

@@ -363,6 +363,7 @@ export const makeSocket = ({
     })
 
 	return {
+        type: 'legacy',
         ws,
         updateKeys: (info: { encKey: Buffer, macKey: Buffer }) => authInfo = info,
         waitForSocketOpen,

src/Socket/socket.ts

@@ -540,6 +540,7 @@ export const makeSocket = ({
     ev.on('creds.update', update => Object.assign(creds, update))
 
 	return {
+        type: 'md',
         ws,
         ev,
         authState: {

src/index.ts

@@ -14,4 +14,6 @@ export { makeWALegacySocket }
 
 export type WASocket = ReturnType<typeof makeWASocket>
 
+export type AnyWASocket = WASocket | WALegacySocket
+
 export default makeWASocket