fix(ui): address PR review comments

- inputwin.c: improve MB_CUR_MAX error message with actionable advice
- inputwin.c: add log_error when input window pad allocation fails
- statusbar.c: add log_warning for invalid cols values
- window.c: simplify _check_subwin_width using CLAMP macro

src/ui/statusbar.c

@@ -40,6 +40,8 @@
 #include <string.h>
 #include <stdlib.h>
 
+#include "log.h"
+
 #ifdef HAVE_NCURSESW_NCURSES_H
 #include <ncursesw/ncurses.h>
 #elif HAVE_NCURSES_H