hardhat_api: Implement hardhat_setCode method

[dutterbutter]

Description:

We need to implement the hardhat_setCode method. This function modifies the bytecode stored at a specified account's address.

// Interface in the `trait`
#[rpc(name = "hardhat_setCode")]
fn set_code(
    &self,
    address: Address, // The address where the given code should be stored
    code: Vec<u8>, // The bytecode to store at the given address
) -> BoxFuture<Result<()>>;

// Actual code in the `impl`
fn set_code(
    &self,
    address: Address,
    code: Vec<u8>,
) -> BoxFuture<Result<()>> {
    // TODO: Solution here
}

Expected command and response:

Command:

curl -X POST http://localhost:8011 \
     -H "Content-Type: application/json" \
     --data '{
       "jsonrpc": "2.0",
       "id": 1,
       "method": "hardhat_setCode",
       "params": ["0x0d2026b3EE6eC71FC6746ADb6311F6d3Ba1C000B", "0xa1a2a3..."]
     }'

Response:

{"jsonrpc":"2.0", "result":true, "id":1}

Requirements:

1. Implement the Method:

   • The method should accept address of type Address and code of type Vec<u8>.
   • Return an acknowledgment once the bytecode has been set for the given address.

2. Unit Tests:

   • Write unit tests ensuring the hardhat_setCode method functions correctly.
   • Test with different addresses and bytecode values, including invalid or non-existent ones.
   • Properly handle potential exceptions and errors.

3. Inline Documentation:

   • Write inline Rust documentation (/// comments) explaining the purpose and usage of the hardhat_setCode method.
   • Include details about parameters, return values, and any possible exceptions or errors.
   • Update SUPPORTED_APIS.md with updated documentation and examples.
   • (Optional) Add request to test_endpoints.http for easier manual verification.

Task Checklist:

• Implement the hardhat_setCode method.
• Write unit tests for the hardhat_setCode method.
• Add inline documentation for the hardhat_setCode method.
• Update documentation for the hardhat_dropTransaction endpoint in SUPPORTED_APIS.md.

Additional Notes:

If you're an external contributor wanting to work on this issue, please comment below to notify us. If you have questions about the requirements or need any assistance related to the implementation, don't hesitate to ask!

[MexicanAce]

Bumping to P1 as it's useful for tests in era-contracts repo