fix: normalize tokenStandard to uppercase in getAssetItemType

[qsysvcore]

Problem

The getAssetItemType function in src/utils/protocol.ts uses a switch statement with uppercase token standard strings ("ERC20", "ERC721", "ERC1155"), but doesn't normalize the input. When the API returns token standards in lowercase or mixed case (e.g., "erc721", "Erc721"), the function incorrectly throws "Unknown schema name" error.

Fix

Added tokenStandard.toUpperCase() normalization at the beginning of the function to ensure case-insensitive matching.

Why this is safe

• The change is minimal (1 line added)
• It makes the function more robust against API responses with different casing
• Aligns with existing patterns in the codebase (e.g., src/sdk/orders.ts uses toUpperCase() when calling this function)
• No breaking changes - all existing valid inputs continue to work
• The TokenStandard type already defines the values in uppercase, so this ensures runtime values match the type definitions