Add USDC Balance and Allowance Management

[Mrwicks00]

Description

Create a reusable component and hooks for managing USDC balance and approvals across the application.

Tasks

• Create a custom hook useUSDCBalance(address) to fetch USDC balance
• Create a custom hook useUSDCAllowance(owner, spender) to fetch allowance
• Create a custom hook useApproveUSDC(spender, amount) for approvals
• Create a USDCBalance component to display user's balance
• Create an ApproveUSDCButton component that:
  • Checks current allowance
  • Shows approval button if needed
  • Handles approval transaction
• Integrate approval checks in voting and prize pool funding flows
• Show approval status in UI
• Handle approval errors

Contract Functions Used

• MockUSDC.balanceOf(address) - Get balance
• MockUSDC.allowance(address, address) - Get allowance
• MockUSDC.approve(address, uint256) - Approve spending

Files to Modify

• frontend/hooks/useUSDCBalance.ts (new file)
• frontend/hooks/useUSDCAllowance.ts (new file)
• frontend/hooks/useApproveUSDC.ts (new file)
• frontend/components/USDCBalance.tsx (new file)
• frontend/components/ApproveUSDCButton.tsx (new file)