Function build_system_prompt 

pub fn build_system_prompt(
    workspace_dir: &Path,
    model_name: &str,
    tools: &[(&str, &str)],
    skills: &[Skill],
    identity_config: Option<&IdentityConfig>,
    bootstrap_max_chars: Option<usize>,
) -> String

Build the default system prompt.

Reports no shell: callers that know their runtime adapter should use build_system_prompt_with_mode_and_autonomy and pass its shell_profile so the model is told which dialect to write.