Add EIP-55 checksum support and validation for EVM addresses

### Problem

Currently, EvmAddress does not support EIP-55 checksum formatting or validation.

This can lead to incorrect address handling and lack of checksum-based error detection when working with EVM-compatible addresses.

### Solution

Proposed improvements:
- Add checksum generation (EIP-55 compliant)
- Add address validation utilities
- Add checksum verification
- Add normalization support

This will improve correctness, safety, and developer experience when interacting with EVM addresses in the SDK.

### Alternatives

_No response_