Added file locks on the mail queue and ticket parse cron jobs to prevent over runs, reverted last commit back to not marking all messages in ticket parse as read

cron_mail_queue.php

@@ -3,6 +3,20 @@
 require_once("config.php");
 require_once("functions.php");
 
+// Get system temp directory
+$temp_dir = sys_get_temp_dir();
+
+// Create the path for the lock file using the temp directory
+$lock_file_path = "{$temp_dir}/itflow_mail_queue_{$installation_id}.lock";
+
+// Check for lock file to prevent concurrent script runs
+if (file_exists($lock_file_path)) {
+    exit("Script is already running. Exiting.");
+}
+
+// Create a lock file
+file_put_contents($lock_file_path, "Locked");
+
 //Initialize the HTML Purifier to prevent XSS
 require("plugins/htmlpurifier/HTMLPurifier.standalone.php");
 $purifier_config = HTMLPurifier_Config::createDefault();
@@ -147,3 +161,6 @@ if (mysqli_num_rows($sql_failed_queue) > 0) {
         }   
     }
 }
+
+// Remove the lock file
+unlink($lock_file_path);