fix(eip-1193): sign personal_sign payloads as raw bytes

[danilaverbena]

Summary

Sign personal_sign challenges as raw bytes instead of UTF-8 text.

Detail

The EIP-1193 provider receives the personal_sign challenge as a hex-encoded byte string. Passing that value directly to viem's signMessage treats values such as 0xdeadbeef as the UTF-8 text "0xdeadbeef", producing a signature over different bytes than the caller requested.

This change passes the challenge through viem's { raw: challenge } form and adds a regression assertion covering the arguments sent to the smart account signer.

Testing

• jest --runInBand src/__tests__/providers/eip-1193/provider.test.ts (19 tests passed)
• tsc --project tsconfig.json --pretty false --noEmit
• eslint src/providers/eip-1193/provider.ts src/__tests__/providers/eip-1193/provider.test.ts
• git diff --check

Documentation

No documentation changes are required; this restores the expected personal_sign behavior.