Missing UnsignedEncryptedInput struct in ICofhe.sol #118

Package version: @fhenixprotocol/cofhe-contracts (latest)

Description:
ICofhe.sol does not define the UnsignedEncryptedInput struct, but it is referenced by downstream packages (e.g. @cofhe/mock-contracts). This causes compilation failures in any project that imports both packages.

Steps to reproduce:

1. Install @fhenixprotocol/cofhe-contracts and @cofhe/mock-contracts in the same Hardhat project
2. Run npx hardhat compile
3. Compilation fails with:

DeclarationError: Declaration "UnsignedEncryptedInput" not found in "@fhenixprotocol/cofhe-contracts/ICofhe.sol"

Expected behavior:
ICofhe.sol should export:

struct UnsignedEncryptedInput {
    uint256 ctHash;
    uint8 securityZone;
    uint8 utype;
}

Current workaround:
Manually patching node_modules/@fhenixprotocol/cofhe-contracts/ICofhe.sol to add the struct.

Additional context:
@cofhe/mock-contracts imports UnsignedEncryptedInput from @fhenixprotocol/cofhe-contracts/ICofhe.sol in MockTaskManager.sol, but the struct does not exist in the source file.