Function register_declared_extensions_in_loader 

pub fn register_declared_extensions_in_loader(
    loader: &mut ModuleLoader,
    current_file: Option<&Path>,
    workspace_root: Option<&Path>,
    current_source: Option<&str>,
    cache: &ExtensionModuleSchemaCache,
)

Register declared extension module artifacts into the given module loader, consulting the provided cache for already-parsed schemas.