Optimize search result finalization by reallocating in place

Replace the malloc/copy/free sequence with a single realloc that
shrinks temp_results to its exact size and returns it directly.  This

* eliminates an extra allocation and memory copy
* simplifies cleanup logic
* retains correct failure handling (temp_results unchanged on realloc
  failure)

Also drop the superfluous trailing space at EOF and add package-lock.json
to version control to lock Node.js dependencies.

similarity_search.c

@@ -307,24 +307,17 @@ SearchResult* search_index(SearchIndex* index, const char* query, float cutoff,
     // Sort results by similarity
     qsort(temp_results, *num_results, sizeof(SearchResult), compare_results);
     
-    // Allocate final result array with exact size
+    // Shrink temp_results to exact size and return it directly
-    SearchResult* results = (SearchResult*)malloc(*num_results * sizeof(SearchResult));
+    SearchResult* results = (SearchResult*)realloc(
+        temp_results, *num_results * sizeof(SearchResult));
     if (!results) {
-        // Free all strings in temp_results
+        // realloc failure – temp_results unchanged, clean up
         for (int i = 0; i < *num_results; i++) {
             free(temp_results[i].string);
         }
         free(temp_results);
         return NULL;
     }
-    
-    // Copy results to final array
-    for (int i = 0; i < *num_results; i++) {
-        results[i].string = temp_results[i].string;
-        results[i].similarity = temp_results[i].similarity;
-    }
-    free(temp_results);
-    
     return results;
 }