nostrdb/cursor: re-apply infinite loop bug fix

since I keep overwriting it by accident

Signed-off-by: William Casarin <jb55@jb55.com>

nostrdb/src/cursor.h

@@ -630,8 +630,7 @@ static inline int consume_until_boundary(struct cursor *cur) {
 		if (is_utf8_byte(c)) {
 			if (!parse_utf8_char(cur, &c, utf8_char_length)) {
 				if (!is_right_boundary(c)){
-                    // TODO: We should work towards handling all UTF-8 characters.
-                    //printf("Invalid UTF-8 code point: %x\n", c);
+					return 0;
 				}
 			}
 		}