Retry ambiguous task starts for active worker polls

[ali-khokhar-nvidia]

What changed?

• Keep one RecordWorkflowTaskStarted or RecordActivityTaskStarted request, including its request ID, across attempt-local deadlines while the original worker poll remains active.
• After such a deadline makes the result ambiguous, keep a subsequent BusyWorkflow inside the same-ID recovery path. History's existing workflow-lock wait paces these attempts while the original operation finishes.
• Return the complete embedded-activity start response when History recognizes a same-ID retry.

An initial BusyWorkflow, queue redelivery, other ResourceExhausted causes, and all definitive errors preserve their existing behavior. A different worker poll still receives a new request ID.

Why?

History can commit a task start while Matching observes its shorter child-context deadline before receiving the response. If the original operation is still finishing, the same-ID recovery attempt can first receive BusyWorkflow. Leaving that recovery path lets a later dispatch create a new request ID; History then returns TaskAlreadyStarted, and no worker receives the committed start response.

The safe recovery boundary is the existing parent worker poll. The Poll*TaskQueue handler creates the record-start request once, and the retry closure reuses that request while each attempt context remains a child of the poll context. When that poll context ends, recovery stops. A later poll enters a new handler invocation and creates a new request ID, so the recovered response can return only through the original poll and cannot be transferred to another worker. Fixes #11733.

How did you test it?

• built
• run locally and tested manually
• covered by existing tests
• added new unit test(s)
• added new functional test(s)

go test -tags disable_grpc_modules,test_dep ./service/matching \
  -run 'TestMatchingEngine_(Classic|Pri|Fair)_Suite/.*Record.*TaskStarted.*|TestRecordTaskStartedWithRetryStopsAtExistingBoundaries' \
  -count=1

go test -tags disable_grpc_modules,test_dep \
  ./service/history/api/recordactivitytaskstarted \
  -run 'TestRecordActivityTaskStarted_DuplicateRequest' \
  -count=1

go vet -tags disable_grpc_modules,test_dep \
  ./service/matching ./service/history/api/recordactivitytaskstarted