Function build_oxicode_engine 

pub async fn build_oxicode_engine(
    embedding_provider: Option<Arc<dyn EmbeddingProvider>>,
    hook_runner: Option<Arc<dyn HookRunner>>,
) -> Result<Oxicode>

This is the new entry point for oxicode-cli run modes. It uses oxicode-fs adapters and OxicodeBuilder::with_port_* to construct an Oxicode with persistence, auth, config, and skills wired. The legacy App::new path is still used by the interactive TUI during the migration period.

use oxicode::build_oxicode_engine;
let oxicode = build_oxicode_engine(None, None).await?;
println!("providers: {}", oxicode.providers().names().len());