As an AntTP user
I want to be able to encrypt and decrypt data over MCP and gRPC endpoints
So that I can encrypt/decrypt data in the same way as the crypto REST API

Given crypto_controller.rs already exists and is used for encrypting and decrypting data over the REST API
When adding support to encrypt/decrypt data using MCP or gRPC API
Then use crypto_controller.rs as an example on how to integrate with crypto_service.rs for the 'encrypt_map' and 'decrypt_map' functions
And update crypto_handler.rs to add 'encrypt' and 'decrypt' functions which is a similar format to its 'sign' and 'verify' function

Given crypto.proto already exists and is used to sign/verify signatures over gRPC
When adding support for encrypting/decrypting data
Then update crypto.proto to include new Encrypt and Decrypt RPC services
And add CryptoContent, CryptoContentRequest and CryptoContentResponse
And update CryptoRequest/CryptoResponse to make public_key optional 
And use the below as an example:

```
service CryptoService {
  rpc Verify(CryptoRequest) returns (CryptoResponse);
  rpc Sign(CryptoRequest) returns (CryptoResponse);
  rpc Encrypt(CryptoContentRequest) returns (CryptoContentResponse);
  rpc Decrypt(CryptoContentRequest) returns (CryptoContentResponse);
}

message Crypto {
  string data = 1;
  optional string signature = 2;
  bool verified = 3;
}

message CryptoRequest {
  optional string public_key = 1;
  repeated Crypto crypto = 2;
}

message CryptoResponse {
  optional string public_key = 1;
  repeated Crypto crypto = 2;
}

message CryptoContent {
  string data = 1;
  optional string content = 2;
}

message CryptoContentRequest {
  optional string public_key = 1;
  repeated CryptoContent crypto_content = 2;
}

message CryptoContentResponse {
  optional string public_key = 1;
  repeated CryptoContent crypto_content = 2;
}
```

Given crypto_tool.rs already exists and is used to sign/verify signatures over MCP
When adding support for encrypting/decrypting data
Then use crypto_controller.rs as an example on how to integrate with crypto_service.rs for the 'encrypt_map' and 'decrypt_map' function
And update crypto_tool.rs to add a 'encrypt' and 'decrypt' functions which is similar to its 'verify_signatures'/'create_signatures' functions

Implementation Notes

- Place any unit tests at the bottom of the same file as the associated production code
- Increment patch version of anttp package in Cargo.toml
- Create a copy of this issue description and save to /spec using the name of this issue as the filename (with lower underscore case, starting with the 5 char padded issue number, e.g. 00001_issue_title.txt)
- Update unit tests to validate the changes

Amendments

Given the data_map is built the same way as a Crypto map in multiple functions is crypto_handler.rs
When refactoring the code to reduce duplication
Then extract the duplicate logic to build_crypto_data_map function

Given the data_map is built the same way as a CryptoContent map in multiple functions is crypto_handler.rs
When refactoring the code to reduce duplication
Then extract the duplicate logic to build_crypto_content_data_map function