Fix: Make sure add-ref adds lang as a property of the lemma

It was previously adding the lang property to the reference.

index/heidegger-index.yml

@@ -3530,6 +3530,11 @@ Pindar:
     - start: 108
     - start: 110
   type: p
+Pizza:
+  lang: ita
+  references:
+    zz:
+    - start: 1
 Plato:
   metadata:
     urn: urn:cts:greekLit:tlg0059

index/index.py

@@ -38,7 +38,7 @@ def add_ref(
     if isinstance(ref, list):
         # Allow ref to be a list, call add_ref for each item and terminate function
         for r in ref:
-            add_ref(lemma, work, r, lemma_type, ref_type, betacode)
+            add_ref(lemma, work, r, lemma_type, ref_type, lang, betacode)
         return
 
     try:
@@ -55,10 +55,6 @@ def add_ref(
     m = REF_REGEX.search(str(ref).strip())
     if not m and ref != "whole":
         raise click.BadParameter(f"Reference '{ref}' is not recognized")
-
-    # Validation: lang
-    if lang:
-        validate_iso639_3_lang(lang)
 
     if betacode:
         lemma = beta_to_uni(lemma)
@@ -80,9 +76,6 @@ def add_ref(
     if ref_type:
         ref_dict["type"] = ref_type
 
-    if lang:
-        ref_dict["lang"] = lang
-
     # Determine whether that lemma is already in the index
     try:
         lemma_entry = index[lemma]
@@ -150,6 +143,11 @@ def add_ref(
 
         lemma_entry["references"] = refs
 
+    # Validation: lang
+    if lang:
+        validate_iso639_3_lang(lang)
+        lemma_entry["lang"] = lang
+
     index[lemma] = lemma_entry
 
     with open(INDEX_FILE, "w") as f: