Initial rebrand: @polkadot -> @pezkuwi (14 packages)

- Package namespace: @polkadot/* -> @pezkuwi/*
- Repository: polkadot-js/common -> pezkuwichain/pezkuwi-common
- Author: Pezkuwi Team <team@pezkuwichain.io>

Core packages:
- @pezkuwi/util (utilities)
- @pezkuwi/util-crypto (crypto primitives)
- @pezkuwi/keyring (account management)
- @pezkuwi/networks (chain metadata)
- @pezkuwi/hw-ledger (Ledger hardware wallet)
- @pezkuwi/x-* (10 polyfill packages)

Total: 14 packages
Upstream: polkadot-js/common v14.0.1

packages/util-crypto/src/sr25519/vrfSign.ts

@@ -0,0 +1,24 @@
+// Copyright 2017-2025 @polkadot/util-crypto authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import type { Keypair } from '../types.js';
+
+import { randomBytes } from '@noble/hashes/utils';
+import * as sr25519 from '@scure/sr25519';
+
+import { u8aToU8a } from '@pezkuwi/util';
+
+const EMPTY_U8A = new Uint8Array();
+
+/**
+ * @name sr25519VrfSign
+ * @description Sign with sr25519 vrf signing (deterministic)
+ */
+export function sr25519VrfSign (message: string | Uint8Array, { secretKey }: Partial<Keypair>, context: string | Uint8Array = EMPTY_U8A, extra: string | Uint8Array = EMPTY_U8A): Uint8Array {
+  if (secretKey?.length !== 64) {
+    throw new Error('Invalid secretKey, expected 64-bytes');
+  }
+
+  return sr25519.vrf.sign(u8aToU8a(message), secretKey, u8aToU8a(context), u8aToU8a(extra), randomBytes);
+  // return vrfSign(secretKey, u8aToU8a(context), u8aToU8a(message), u8aToU8a(extra));
+}