Implement Global Transaction Toast Notifications

[Alhaji-naira]

Description:
Submitting a transaction on the Stellar network takes a few seconds. To prevent users from clicking buttons multiple times or thinking the app is frozen, we need global toast notifications to provide real-time feedback on transaction lifecycles.

Acceptance Criteria:

• Integrate a toast notification library (e.g., react-hot-toast or sonner).
• When a user submits a swap or liquidity transaction via Freighter, immediately display a "Transaction Pending..." toast with a loading spinner.
• Listen for the transaction response from the Soroban contract.
• Update the toast to a green "Transaction Successful" (with a link to Stellar Expert for the transaction hash) or a red "Transaction Failed" message based on the on-chain result.

[Damola-Sodiq]

@Alhaji-naira Hi i would like to be contribute to this project, so could you please assign this to me?