contrib/google_adk_agents: stream LlmResponse chunks via Workflow Streams #5016

Job	Run time
check-protos	7m 12s
cloud-test	1m 49s
test-latest-deps	10m 4s
features-tests / test	8m 11s
build-lint-test (3.10, windows-latest)	17m 14s
build-lint-test (3.10, ubuntu-arm)	11m 15s
build-lint-test (3.10, macos-intel)	20m 11s
build-lint-test (3.10, macos-arm)	9m 45s
build-lint-test (3.14, macos-arm)	9m 9s
build-lint-test (3.10, ubuntu-latest)	14m 4s
build-lint-test (3.14, windows-latest)	18m 40s
build-lint-test (3.14, ubuntu-latest)	14m 25s
build-lint-test (3.14, ubuntu-arm)	10m 31s
build-lint-test (3.14, macos-intel)	17m 55s
	2h 50m 25s

Provide feedback