[expansion] Adding the ability to search address dictionary phrases with a NULL language, will return phrases in any language

src/trie.h

@@ -129,6 +129,7 @@ typedef struct trie_prefix_result {
     size_t tail_pos;
 } trie_prefix_result_t;
 
+#define ROOT_PREFIX_RESULT (trie_prefix_result_t) {ROOT_NODE_ID, 0}
 #define NULL_PREFIX_RESULT (trie_prefix_result_t) {NULL_NODE_ID, 0}
 
 trie_prefix_result_t trie_get_prefix(trie_t *self, char *key);