services(anthropic): allow setting enable prompt caching via frame

src/pipecat/frames/frames.py

@@ -186,6 +186,13 @@ class LLMSetToolsFrame(DataFrame):
     tools: List[dict]
 
 
+@dataclass
+class LLMEnablePromptCachingFrame(DataFrame):
+    """A frame to enable/disable prompt caching in certain LLMs.
+    """
+    enable: bool
+
+
 @dataclass
 class TTSSpeakFrame(DataFrame):
     """A frame that contains a text that should be spoken by the TTS in the