title check for whitespace for title

Signed-off-by: samin-z <samin.zavarkesh@gmail.com>

Author: samin-z

lib/Validators/BaseValidator.php

@@ -104,7 +104,15 @@ private function not_null($value): bool {
 	 * @return bool
 	 */
 	private function not_empty($value): bool {
-		return !empty($value);
+		// Treat string zero as a valid non-empty value while still rejecting other empty values
+		if ($value === '0') {
+			return true;
+		}
+
+        if (is_string($value)) {
+            return strlen(trim($value)) > 0;
+        }
+        return !empty($value);
 	}
 
 	/**