patch 9.1.1645: fuzzy.c can be further improved

Problem:  fuzzy.c can be further improved
Solution: Fix memory leak and refactor it (glepnir).

Optimize performance and memory allocation:

- Fix memory leak in fuzzy_match_in_list.
- using single memory allocation in match_positions
- Improve has_match performance and add null pointer checks

closes: #18012

Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/version.c

@@ -719,6 +719,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1645,
 /**/
     1644,
 /**/