Display User Balance Using starknet-react After Wallet Connect

#### 📌 Description:
After the user has connected their wallet (via Invisible SDK or Cartridge Controller), display their **token balance** next to their **wallet address** in the UI using `starknet-react`.

This balance display must adhere to the **existing style guide** and be reactive to wallet connection status.

#### 🧠 Context:
Now that wallet connection flows are being implemented, the user interface should give immediate feedback on the wallet’s status, including **address** and **token balance**. This improves transparency and UX across the app.

#### 🧭 Proposed Actions:
1. Use `starknet-react` to detect connected wallet (`useStarknetAccount`)
2. Fetch the native token balance using `useBalance` or a custom hook
3. Display:
- Formatted token balance (e.g., `10.25 ETH`)
4. Place this display **next to** or **under** the address in the existing UI
5. Style the component based on the app’s current design system (font, color, spacing)
6. Ensure the layout works well across all screen sizes

#### ✅ Acceptance Criteria:
- Wallet balance is fetched and displayed using `starknet-react`
- Display updates/reacts automatically when wallet is connected
- Adheres to visual and functional style guidelines
- UI is responsive and readable on both desktop and mobile
- No unnecessary re-renders or flickers in data fetching

#### 🕒 Timeframe:
No strict deadline, but this task is essential for polishing the wallet UX and should follow after the connection flows are implemented.