Add compact chat completion trace fetcher #6699

Job	Run time
build-and-check	2m 57s
test-integration-packages/internal	1m 2s
test-integration-packages/billing	1m 7s
test-integration-cli	39s
test-integration-common	45s
test-integration-web	49s
test-integration-packages/agent-runtime	39s
test-common	39s
test-packages/agent-runtime	51s
test-packages/billing	42s
test-packages/internal	52s
test-.agents	50s
test-integration-sdk	1m 8s
test-cli	1m 0s
test-web	1m 0s
test-sdk	46s
	15m 46s

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