Function build_sidecar_entry 

pub fn build_sidecar_entry<F>(
    query: &AnalyzedQuery,
    bindings: &BTreeMap<String, HttpParamBinding>,
    scythe_module: &str,
    scythe_fn: &str,
    is_async: bool,
    lang_type_for: F,
) -> SidecarEntry
where
    F: Fn(&str, bool) -> String,

Build a sidecar entry from an AnalyzedQuery and a per-param binding map.

lang_type_for resolves a (neutral_type, nullable) pair to the target language’s type string. We deliberately take it as a closure so the SQL module stays language-agnostic — callers supply scythe’s own backend-aware resolver per language.