Function run_mutation_testing 

pub async fn run_mutation_testing<FEN: FoundryEvmNetwork>(
    config: Arc<Config>,
    output: &ProjectCompileOutput<MultiCompiler>,
    evm_opts: EvmOpts,
    backend: Backend<FEN>,
    executor_builder: ExecutorBuilder<FEN>,
    mutation_config: MutationRunConfig,
) -> Result<MutationRunResult>

Run mutation testing on the project.

This function encapsulates the mutation testing logic that was previously in the test command. It handles:

• Filtering source files based on patterns
• Per-file mutation handling with caching
• Parallel mutation execution
• Result aggregation and reporting