Important

Adds RCC credit balance display feature with backend fetching and frontend UI updates, including tests for new functionality.

• Behavior:
  • Adds creditBalance() method to CloudAPI in CloudAPI.ts to fetch RCC credit balance.
  • Handles requestRooCreditBalance in webviewMessageHandler.ts to fetch and return balance to webview.
  • Displays balance in RooBalanceDisplay component when authenticated.
• Tests:
  • Adds CloudAPI.creditBalance.spec.ts to test creditBalance() method.
  • Adds webviewMessageHandler.rooBalance.spec.ts to test message handling for balance requests.
  • Adds RooBalanceDisplay.spec.tsx to test balance display component.
  • Updates ApiOptions.spec.tsx to test balance display in ApiOptions component.
• UI Components:
  • Adds RooBalanceDisplay.tsx to display formatted balance with a link to billing.
  • Updates ApiOptions.tsx to conditionally show RooBalanceDisplay when provider is roo and authenticated.

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