feat(classifier): has_short_latin_name() helper for drop-logic

includes/class-classifier.php

@@ -243,4 +243,23 @@ final class Classifier
         }
         return false;
     }
+
+    /**
+     * Checks whether the form's name field contains 1-3 ASCII alphanumeric characters
+     * (typical bot pattern: "OB", "MU", "A1B"). Used by drop hard-rule.
+     *
+     * Looks first at canonical CF7 keys (your-name, name, имя, fio), then falls back to
+     * the value-based heuristic in FieldDetector::find_name(). Returns false if no name
+     * field is present (i.e. forms without a name field are immune to this rule).
+     *
+     * @param array<string,string|string[]> $fields CF7 posted_data
+     */
+    public static function has_short_latin_name(array $fields): bool
+    {
+        $name = self::pick_field($fields, ['your-name', 'name', 'имя', 'fio']);
+        if ($name === '') $name = FieldDetector::find_name($fields);
+        $name = trim($name);
+        if ($name === '') return false;
+        return (bool)preg_match('/^[A-Za-z0-9]{1,3}$/', $name);
+    }
 }