feat: Add /force-encryption command and update message handling

Implement /force-encryption command to configure forced encryption
settings with on|off and policy resend-to-confirm|block options.

The changes enhance user experience by clarifying encryption requirements
and providing actionable commands. Users can now press Enter again to
confirm unencrypted messages in resend-to-confirm mode.

src/command/cmd_defs.c

@@ -2746,7 +2746,7 @@ static const struct cmd_t command_defs[] = {
     },
 
     { CMD_PREAMBLE("/force-encryption",
-                   parse_args, 1, 3, &cons_encryption_settings)
+                   parse_args, 1, 3, &cons_encryption_setting)
       CMD_MAINFUNC(cmd_force_encryption)
       CMD_TAGS(
               CMD_TAG_CHAT)

src/ui/console.c

@@ -2893,9 +2893,9 @@ cons_privacy_setting(void)
 }
 
 void
-cons_encryption_settings(void)
+cons_encryption_setting(void)
 {
     cons_show("Force encryption                                           : %sabled", prefs_get_boolean(PREF_FORCE_ENCRYPTION) ? "en" : "dis");
 
     cons_show("Force encryption mode                                      : %s", prefs_get_string(PREF_FORCE_ENCRYPTION_MODE));
-}
+}

src/ui/ui.h

@@ -351,7 +351,7 @@ void cons_theme_properties(void);
 void cons_theme_colours(void);
 void cons_show_tlscert(const TLSCertificate* cert);
 void cons_show_tlscert_summary(const TLSCertificate* cert);
-void cons_encryption_settings(void);
+void cons_encryption_setting(void);
 
 void cons_alert(ProfWin* alert_origin_window);
 void cons_remove_alert(ProfWin* window);

tests/unittests/ui/stub_ui.c

@@ -675,6 +675,11 @@ inp_readline(void)
     return NULL;
 }
 
+void
+inp_set_line(const char* const new_line)
+{
+}
+
 void
 inp_nonblocking(gboolean reset)
 {
@@ -1157,6 +1162,11 @@ cons_privacy_setting(void)
 {
 }
 
+void
+cons_encryption_setting(void)
+{
+}
+
 void
 cons_show_bookmarks_ignore(gchar** list, gsize len)
 {