feat: track history being stored

This is done because sometimes we receive history after the first connect too, and to ensure the "isLatest" flag is accurate -- we ensure no history was received previously

src/Types/Message.ts

@@ -188,4 +188,6 @@ export type MediaDecryptionKeyInfo = {
     iv: Buffer
     cipherKey: Buffer
     macKey?: Buffer
-}
+}
+
+export type MinimalMessage = Pick<proto.IWebMessageInfo, 'key' | 'messageTimestamp'>