Update dependencies and enhance App component functionality

- Added new dependencies: @polkadot/util and @gear-js/api to package.json and example/package.json.
- Implemented a test function in App component to interact with GearApi for balance transfer.
- Updated transaction signing logic to support both raw and payload types.
- Refactored Wallet class to improve socket connection handling and transaction management.
- Enhanced WalletStore by removing unnecessary listener setup code.

package.json

@@ -56,6 +56,7 @@
   },
   "homepage": "https://gitlab.mind-dev.com/pb/varan-connect#readme",
   "dependencies": {
+    "@polkadot/util": "13.5.7",
     "@twa-dev/sdk": "^8.0.2"
   },
   "devDependencies": {