fix: unquote self-referential annotation for pyupgrade

pyupgrade --py314-plus rewrites the quoted return annotation added in #345,
failing pre-commit. The project requires Python 3.14, where annotations are
evaluated lazily (PEP 649), so the unquoted form imports fine.

agentic_security/refusal_classifier/hybrid_classifier.py

@@ -86,7 +86,7 @@ class HybridRefusalClassifier:
         detector: RefusalDetector,
         weight: float = 1.0,
         name: str | None = None,
-    ) -> "HybridRefusalClassifier":
+    ) -> HybridRefusalClassifier:
         """Add a detection method with specified weight.
 
         Args: