fix ncurses termination handling

[piotrkochan]

PhotoRec often corrupted the terminal when killed with Ctrl+C in ncurses mode. Users had to run reset or stty sane to restore normal terminal functionality after interrupting the program. This PR fixes that.

[cgsecurity]

All functions called by end_ncurses() may not be signal-safe but it seems to work without side effect under Linux Fedora 41 with this shorted patch:

--- /home/kmaster/src/git/testdisk/src/phmain.c 2023-02-19 08:04:54.627483562 +0100
+++ ./phmain.c 2025-09-28 14:11:26.295956987 +0200
@@ -112,6 +112,9 @@
log_flush();
if(need_to_stop==1)
{
+#ifdef HAVE_NCURSES

• end_ncurses();
  +#endif
  action.sa_handler=SIG_DFL;
  sigaction(sig,&action,NULL);
  kill(0, sig);

src/testdisk.c will need to get a similar patch.
Under which OS have you tested this patch ?

[piotrkochan]

@cgsecurity

piotr@pjoter:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 24.04.3 LTS
Release:        24.04
Codename:       noble
piotr@pjoter:~$ echo $SHELL
/bin/bash