poststartup script moved to extra container, non init

elasticsearch/values.yaml

@@ -189,12 +189,12 @@ extraContainers:
             echo "[template-loader] Attempt $i: ES not ready, sleeping..."
             sleep "${RETRY_INTERVAL:-5}"
           done
-          echo "[template-loader] Applying templates..."
+          echo "[template-loader] Applying index templates..."
           for idx in "chat:$TEMPLATE_PATH_1" "message:$TEMPLATE_PATH_2" "user:$TEMPLATE_PATH_3"; do
             name="${idx%%:*}"
             path="${idx##*:}"
-            echo "[template-loader] Applying $name from $path..."
-            curl -X PUT "$ES_URL/$name" \
+            echo "[template-loader] Applying template: $name from $path..."
+            curl -X PUT "$ES_URL/_index_template/$name" \
               -H 'Content-Type: application/json' \
               --data-binary @"$path"
           done