Flash if history search found nothing

This makes it clearer that we're at the end.

Fixes #7362.

CHANGELOG.rst

@@ -124,6 +124,7 @@ Interactive improvements
 -  ``open`` no longer hangs indefinitely as a bug in ``xdg-open`` has been worked around (#7215).
 -  Long command lines no longer add a blank line after execution (#6826) and behave better with backspace (#6951).
 -  ``functions -t`` works as documented (#6985).
+-  History search now flashes when it found no more results (#7362)
 
 New or improved bindings
 ^^^^^^^^^^^^^^^^^^^^^^^^

src/reader.cpp

@@ -3141,6 +3141,10 @@ void reader_data_t::handle_readline_command(readline_cmd_t c, readline_loop_stat
                         ? history_search_direction_t::backward
                         : history_search_direction_t::forward;
                 bool found = history_search.move_in_direction(dir);
+
+                // Signal that we've found nothing
+                if (!found) flash();
+
                 if (!found && !was_active_before) {
                     history_search.reset();
                     break;