Function build_capability_op_info 

pub fn build_capability_op_info(
    op: &CapabilityOp,
    types: &HashMap<String, Arc<TypeDecl>>,
    tys: &Arc<Types>,
) -> CapabilityOpInfo

#926: build a checker-facing CapabilityOpInfo from a capability op’s AST, with the op’s own type parameters (if any) resolved as Ty::Var rather than ground types — a call site substitutes a concrete Ty for each before checking. Shared by every site that reconstructs CapabilityInfo from a CapabilityDecl (local capabilities, test/property bodies targeting a context) so the vars-in-scope treatment can’t drift.