feat: add sncrypto client side packages

packages/sncrypto-common/src/AES-GCM/Aes256GcmInput.ts

@@ -0,0 +1,15 @@
+import { HexString } from '../Types/HexString'
+import { Unencrypted } from '../Types/Unencrypted'
+
+/**
+ * @param unencrypted -- UTF-8 string or a `string` with `encoding`
+ * @param iv initialization vector as a hex string
+ * @param key encryption key as a hex string
+ * @param aad additional authenticated data as a hex string
+ */
+export type Aes256GcmInput<EncodingType> = {
+  unencrypted: Unencrypted<EncodingType>
+  iv: HexString
+  key: HexString
+  aad?: HexString
+}