chore: move signData to file used by tests only

Author: sampaiodiego

packages/core/src/index.ts

@@ -22,7 +22,6 @@ export type { ProtocolVersionKey, SignedJson } from './utils/signJson';
 export {
 	signJson,
 	isValidAlgorithm,
-	signData,
 } from './utils/signJson';
 
 // Binary data utilities

packages/core/src/utils/keys.spec.ts

@@ -1,8 +1,6 @@
-import { afterEach, beforeEach, describe, expect, it, spyOn } from 'bun:test';
-import fs from 'node:fs/promises';
+import { describe, expect, it } from 'bun:test';
 import nacl from 'tweetnacl';
 import { EncryptionValidAlgorithm } from '../types';
-import { toUnpaddedBase64 } from './binaryData';
 import { generateKeyPairs, generateKeyPairsFromString } from './keys';
 
 describe('keys', () => {

packages/core/src/utils/keys.ts

@@ -1,7 +1,20 @@
 import nacl from 'tweetnacl';
 import { EncryptionValidAlgorithm } from '../types';
 import type { SigningKey } from '../types';
-import { signData } from './signJson';
+
+// these functions are used by tests only
+
+async function signData(
+	data: string | Uint8Array,
+	signingKey: Uint8Array,
+): Promise<Uint8Array> {
+	const signature = nacl.sign.detached(
+		typeof data === 'string' ? new TextEncoder().encode(data) : data,
+		signingKey,
+	);
+
+	return signature;
+}
 
 export async function generateKeyPairs(
 	seed: Uint8Array,