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/src/is/u8a.ts

@@ -0,0 +1,25 @@
+// Copyright 2017-2025 @polkadot/util authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+/**
+ * @name isU8a
+ * @summary Tests for a `Uint8Array` object instance.
+ * @description
+ * Checks to see if the input object is an instance of `Uint8Array`.
+ * @example
+ * <BR>
+ *
+ * ```javascript
+ * import { isUint8Array } from '@pezkuwi/util';
+ *
+ * console.log('isU8a', isU8a([])); // => false
+ * ```
+ */
+export function isU8a (value?: unknown): value is Uint8Array {
+  // here we defer the instanceof check which is actually slightly
+  // slower than just checking the constrctor (direct instances)
+  return (
+    ((value && (value as Uint8Array).constructor) === Uint8Array) ||
+    value instanceof Uint8Array
+  );
+}