feat(dialogflow-cx): Example implementation of Streaming Detect Intent with continuous microphone input and audio output (#13053)

* feat(dialogflow-cx): Dialogflow CX infinit streaming example with microphone input and speaker output

* chore(dialogflow-cx) Fix restarting the stream after response message was received

* chore(dialogflow-cx): do not capture microphone input when playing audio

* chore(dialogflow-cx): remove unused reset_stream

* chore(dialogflow-cx): Apply Authoring Guideline improvements

* chore(dialogflow-cx): Update dependencies for audio IO streaming

* Update dialogflow-cx/streaming_detect_intent_infinite.py

Update example invocation

Co-authored-by: code-review-assist[bot] <182814678+code-review-assist[bot]@users.noreply.github.com>

* Update dialogflow-cx/streaming_detect_intent_infinite.py

Add validation of agent name

Co-authored-by: code-review-assist[bot] <182814678+code-review-assist[bot]@users.noreply.github.com>

* chore(dialogflow-cx): Fix invocation

* chore(dialogflow-cx): Remove message on quitting with Exit and Quit

* chore(dialogflow-cx): Add region tags

* chore(dialogflow-cx): Improved and cleaned up documentation.

* Update region tags to correct format

* chore(dialoglow-cx): fix race condition when _output_audio_stream is not yet available

* chore(dialogflow-cx): Use correct codeblock syntax in docstring

* chore(dialogflow-cx): Code cleanup and refactoring addressing comments

* chore(dialogflow-cx): Code cleanup addressing code review suggestions

* chore(dialogflow-cx): Added default constants

* chore(dialogflow-cx): restructured audio stream creation

* feat(dialogflow-cx): Add test for streaming_detect_intent_infinite

* chore(dialogflow-cx): Add requirements specifiers for termcolor to support Python 3.8

* chore(dialogflow-cx): add pytest-asyncio as dependency for pytest

* chore(dialogflow-cx): Python 3.8+ compatibility

* chore(dialogflow-cx): Fix linting issue

* chore(dialogflow-cx): Fix mocking for testing in Python 3.8

---------

Co-authored-by: code-review-assist[bot] <182814678+code-review-assist[bot]@users.noreply.github.com>
Co-authored-by: Katie McLaughlin <katie@glasnt.com>

Author: 3 people

dialogflow-cx/requirements-test.txt

@@ -1 +1,2 @@
 pytest==8.2.0
+pytest-asyncio==0.21.1

dialogflow-cx/requirements.txt

@@ -1,5 +1,8 @@
-google-cloud-dialogflow-cx==1.37.0
+google-cloud-dialogflow-cx==1.38.0
 Flask==3.0.3
 python-dateutil==2.9.0.post0
 functions-framework==3.8.2
 Werkzeug==3.0.6
+termcolor==2.5.0; python_version >= "3.9"
+termcolor==2.4.0; python_version == "3.8"
+pyaudio==0.2.14