Update OpenAIRealtimeLLMService to work with LLMContext and LLMContextAggregatorPair (cont'd).

Add warning about no longer pushing `TTSTextFrame`s.

CHANGELOG.md

@@ -82,6 +82,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   by context aggregators, to update its internal state. Listen for
   `LLMContextFrame`s for context updates.
 
+  Finally, `LLMTextFrame`s are no longer pushed from `OpenAIRealtimeLLMService`
+  when it's configured with `output_modalities=['audio']`. If you need
+  to process its output, listen for `TTSTextFrame`s instead.
+
 - Expanded support for universal `LLMContext` to `GeminiLiveLLMService`.
   As a reminder, the context-setup pattern when using `LLMContext` is:
 

src/pipecat/services/openai/realtime/llm.py

@@ -885,8 +885,11 @@ class OpenAIRealtimeLLMService(LLMService):
             "    context_aggregator.assistant(),\n"
             "  ]\n"
             ")\n\n"
-            "Once you've done that (if needed), you can dismiss this warning "
-            "by updating to the new context-setup pattern:\n\n"
+            "Also, LLMTextFrames are no longer pushed from "
+            "OpenAIRealtimeLLMService when it's configured with "
+            "output_modalities=['audio']. Listen for TTSTextFrames instead.\n\n"
+            "Once you've made the appropriate changes (if needed), you can"
+            "dismiss this warning by updating to the new context-setup pattern:\n\n"
             "  context = LLMContext(messages, tools)\n"
             "  context_aggregator = LLMContextAggregatorPair(context)\n"
         )