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

@@ -2729,6 +2729,7 @@ static const struct cmd_t command_defs[] = {
               { "os on|off", "Choose whether to include the OS name if a user asks for software information (XEP-0092)." }
               )
       CMD_EXAMPLES(
+              "/privacy",
               "/privacy logging off",
               "/privacy os off")
     },
@@ -2744,6 +2745,31 @@ static const struct cmd_t command_defs[] = {
               "Redraw user interface. Can be used when some other program interrupted profanity or wrote to the same terminal and the interface looks \"broken\"." )
     },
 
+    { CMD_PREAMBLE("/force-encryption",
+                   parse_args, 1, 3, &cons_encryption_setting)
+      CMD_MAINFUNC(cmd_force_encryption)
+      CMD_TAGS(
+              CMD_TAG_CHAT)
+      CMD_SYN(
+              "/force-encryption",
+              "/force-encryption on|off",
+              "/force-encryption policy resend-to-confirm|block")
+      CMD_DESC(
+              "Configure forced encryption for outgoing messages in CProof. "
+              "When enabled, restricts sending unencrypted messages based on the specified policy. "
+              "Run without arguments to display current settings.")
+      CMD_ARGS(
+              { "on|off", "Enable or disable forced encryption. When enabled, restricts unencrypted messages per the policy. When disabled, allows sending unencrypted messages without restrictions." },
+              { "policy resend-to-confirm|block", "Set the policy for unencrypted messages when forced encryption is enabled. 'resend-to-confirm' requires pressing Enter again to confirm sending an unencrypted message (default). 'block' prevents sending unencrypted messages entirely." }
+              )
+      CMD_EXAMPLES(
+              "/force-encryption",
+              "/force-encryption on",
+              "/force-encryption off",
+              "/force-encryption policy resend-to-confirm",
+              "/force-encryption policy block")
+    },
+
     // NEXT-COMMAND (search helper)
 };
 

src/command/cmd_funcs.c

@@ -10633,3 +10633,22 @@ cmd_vcard_save(ProfWin* window, const char* const command, gchar** args)
     cons_show("User vCard uploaded");
     return TRUE;
 }
+
+gboolean
+cmd_force_encryption(ProfWin* window, const char* const command, gchar** args)
+{
+    if (g_strv_length(args) == 1 && (g_strcmp0(args[0], "on") == 0 || g_strcmp0(args[0], "off") == 0)) {
+        _cmd_set_boolean_preference(args[0], "Forces encryption", PREF_FORCE_ENCRYPTION);
+    } else if (g_strv_length(args) == 2 && g_strcmp0(args[0], "policy") == 0) {
+        if (g_strcmp0(args[1], "resend-to-confirm") != 0 && g_strcmp0(args[1], "block") != 0) {
+            cons_show_error("Invalid policy: \"%s\". See '/help force-encryption' for details.", args[1]);
+            return TRUE;
+        }
+        prefs_set_string(PREF_FORCE_ENCRYPTION_MODE, args[1]);
+        cons_show("Force encryption policy has been set to \"%s\".", args[1]);
+    } else {
+        cons_bad_cmd_usage(command);
+    }
+
+    return TRUE;
+}

src/command/cmd_funcs.h

@@ -269,5 +269,6 @@ gboolean cmd_vcard_photo(ProfWin* window, const char* const command, gchar** arg
 gboolean cmd_vcard_refresh(ProfWin* window, const char* const command, gchar** args);
 gboolean cmd_vcard_set(ProfWin* window, const char* const command, gchar** args);
 gboolean cmd_vcard_save(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_force_encryption(ProfWin* window, const char* const command, gchar** args);
 
 #endif