Add standalone activity metrics

[fretz12]

What changed?

Add standalone activity metrics

Why?

Need standalone activity metrics for observability purposes

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)

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Note

Adds comprehensive metrics and payload-size recording for standalone activities, introducing contextual request wrappers and wiring metrics through state transitions, timeout executors, and history APIs.

• Activity component/state machine:
  • Introduces RequestWithContext carrying Token, MetricsHandler, NamespaceName, and BreakdownMetricsByTaskQueue and replaces prior request wrappers.
  • Records metrics on schedule, attempts, and terminal transitions (success, fail, cancel, timeouts), including ActivityStartToCloseLatency, ActivityScheduleToCloseLatency, success/fail/cancel/timeout counters, and per-timeout tags.
  • Adds recordPayloadSize(...) to emit payload sizes for input, heartbeat details, results, and failures.
• Timeout and dispatch executors (chasm/lib/activity/activity_tasks.go):
  • Add timeoutTaskExecutorOptions (dynamic config, metrics, namespace registry); resolve namespace and emit timeout metrics during schedule/start/close/heartbeat timeouts and retries.
• Activity handler:
  • Injects metrics.Handler and namespace.Registry; StartActivityExecution emits input payload size on scheduling.
• History APIs (record/respond activity ops):
  • Pass RequestWithContext (token, metrics handler, namespace, breakdown setting) into chasm component calls.
• Tests:
  • Update/add unit tests to validate metric emissions and payload-size recording across transitions and timeouts.

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[fretz12]

cursor review

[bergundy]

Overall this looks really good. I would consider restructuring the code as I suggested to make it easier to follow.

[bergundy]

Approving assuming that the attempt start to close metrics are emitted only when transitioning from a state that is not scheduled.