[lib] add method to parse one-time keys

Summary:
Add method which parses keys to store entire object.
Some context in [ENG-6099](https://linear.app/comm/issue/ENG-6099/parse-one-time-keys-from-identity).

Test Plan: Make sure keys output is correct, and it's possible to create session (later in the stack).

Reviewers: marcin, varun, michal

Reviewed By: marcin, varun

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D10368

lib/shared/crypto-utils.js

@@ -20,7 +20,7 @@ import type {
   CallServerEndpointOptions,
   CallServerEndpoint,
 } from '../utils/call-server-endpoint.js';
-import { values } from '../utils/objects.js';
+import { values, entries } from '../utils/objects.js';
 
 export type InitialNotifMessageOptions = {
   +callServerEndpoint?: ?CallServerEndpoint,
@@ -98,11 +98,20 @@ function getPrekeyValueFromBlob(prekeyBlob: string): string {
   return getPrekeyValue(prekey);
 }
 
+function getOneTimeKeyArray(
+  oneTimeKeys: OLMOneTimeKeys,
+): $ReadOnlyArray<string> {
+  return entries(oneTimeKeys.curve25519).map(([key, value]: [string, string]) =>
+    JSON.stringify({ curve25519: { [key]: value } }),
+  );
+}
+
 export {
   getOneTimeKeyValues,
   getPrekeyValue,
   getOneTimeKeyValuesFromBlob,
   getPrekeyValueFromBlob,
   initialEncryptedMessageContent,
   useInitialNotificationsEncryptedMessage,
+  getOneTimeKeyArray,
 };