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

.gitignore

@@ -0,0 +1,28 @@
+--test-*
+_book/
+build/
+build-*/
+coverage/
+node_modules/
+tmp/
+/import_map.json
+/mod.ts
+.DS_Store
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+.idea
+.npmrc
+.vscode
+.yarn/*
+!.yarn/releases
+!.yarn/plugins
+.pnp.*
+cc-test-reporter
+lerna-debug.log*
+npm-debug.log*
+package-lock.json
+yarn-debug.log*
+yarn-error.log*
+tsconfig.*buildinfo