Function render_composite 

pub fn render_composite<F>(
    bundle: &Value,
    members: &[Value],
    template: &str,
    own_parts: &[Value],
    kind: Kind,
    globals: F,
) -> Result<CompositeOutput, CompositeScopeError>
where
    F: Fn(&str) -> Option<ScopedValue>,

Resolve scoped references into synthetic named parts, then pass those parts through the shared zone-aware composite renderer.