Added STS profile persistence and policy parsing/enforcement (including load/save, upgrades, and expiry rescheduling) to the STS module.

Integrated STS capability handling and connection lifecycle hooks (ignore CAP DEL, trigger upgrades, reschedule on disconnect, new server fields).
Initialized and cleaned up STS state during startup/shutdown to persist policies across sessions.

src/common/zoitechat.c

@@ -49,6 +49,7 @@
 #include "notify.h"
 #include "server.h"
 #include "servlist.h"
+#include "sts.h"
 #include "outbound.h"
 #include "text.h"
 #include "url.h"
@@ -1200,6 +1201,7 @@ xchat_init (void)
 	sound_load ();
 	notify_load ();
 	ignore_load ();
+	sts_init ();
 
 	g_snprintf (buf, sizeof (buf),
 		"NAME %s~%s~\n"				"CMD query %%s\n\n"\
@@ -1352,6 +1354,7 @@ zoitechat_exit (void)
 	sound_save ();
 	notify_save ();
 	ignore_save ();
+	sts_cleanup ();
 	free_sessions ();
 	chanopt_save_all (TRUE);
 	servlist_cleanup ();