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/address/keyDerived.ts

@@ -0,0 +1,22 @@
+// Copyright 2017-2025 @polkadot/util-crypto authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import type { BN } from '@pezkuwi/util';
+
+import { bnToU8a, stringToU8a, u8aConcat } from '@pezkuwi/util';
+
+import { blake2AsU8a } from '../blake2/asU8a.js';
+import { BN_LE_16_OPTS } from '../bn.js';
+import { decodeAddress } from './decode.js';
+
+const PREFIX = stringToU8a('modlpy/utilisuba');
+
+export function createKeyDerived (who: string | Uint8Array, index: bigint | BN | number): Uint8Array {
+  return blake2AsU8a(
+    u8aConcat(
+      PREFIX,
+      decodeAddress(who),
+      bnToU8a(index, BN_LE_16_OPTS)
+    )
+  );
+}