Function is_hcl_language 

pub fn is_hcl_language(lang: &Language) -> bool

Check whether a tree_sitter::Language is the HCL grammar.

Used by crate::repo_map to gate HCL-specific call-edge extraction (terraform_remote_state references and module blocks — R2/R3, Wave 3). Same node-kind-count proxy as is_rust_language.