fix: improve error UI in transaction result

[jinoosss]

What type of PR is this?

• bug

What this PR does:

Summary

• Simplify scanner button hover styles in transaction result to use opacity-based feedback instead of color changes
• Add simulate error banner to Transfer Summary page, separating "Insufficient network fee" (shown in the fee section) from detailed simulation errors (shown in a dedicated error banner), consistent with the Approve Transaction page
• Standardize all .error-message font sizes from 11px to 13px across 11 style files for better readability

Changes

Transaction Result

• Replace color-based hover effect with opacity transition on the scanner (Gnoscan) button

Transfer Summary

• Add simulateErrorBannerMessage prop to display simulation errors in a red banner (ERROR: {message})
• Separate error cases: NetworkFee only shows "Insufficient network fee" for balance issues; simulate errors are shown exclusively in the banner
• Exclude simulate errors from isNetworkFeeError to prevent duplicate error indicators
• Fix bottom content overlap with fixed buttons by using a spacer element instead of padding-bottom

Error Message Font Size

• Override .error-message font-size to 13px in: NetworkFee, StorageDeposit, ApproveTransaction, ApproveSignedDocument, BroadcastMultisigTransaction, CreateMultisigTransaction, TransferSummary, NFTTransferSummary, AddressInput, MemoInput, CustomNetworkInput