fix(telemetry): add common gen_ai attributes to event loop cycle spans

[giulio-leone]

Summary

start_event_loop_cycle_span() was the only span start method that did not call _get_common_attributes(), causing event loop cycle spans to lack gen_ai.system / gen_ai.provider.name and gen_ai.operation.name attributes.

This is inconsistent with start_model_invoke_span, start_tool_call_span, start_agent_span, and start_multiagent_span, all of which include these common attributes. Downstream OTEL tooling (collectors, exporters, redaction processors) may rely on these attributes for filtering or policy decisions.

Changes

• Added _get_common_attributes(operation_name="execute_event_loop_cycle") call in start_event_loop_cycle_span()
• Updated existing tests to expect the new common attributes in both legacy and latest convention modes

Testing

All 74 tracer tests pass (including 5 event_loop_cycle-specific tests).

Closes #1876

[giulio-leone]

Friendly ping — adds standard gen_ai.* OpenTelemetry semantic convention attributes to event loop cycle spans for better observability integration.

[giulio-leone]

Refreshed onto main @ fd8168a (v1.32.0+2) — 2026-03-23

Root cause confirmed still live: start_event_loop_cycle_span still builds its attribute dict as a bare {"event_loop.cycle_id": …} literal, bypassing _get_common_attributes, so event loop cycle spans are missing the gen_ai.operation.name / gen_ai.system / gen_ai.provider.name attributes that every other span in the telemetry layer carries.

Fix: Call _get_common_attributes(operation_name="execute_event_loop_cycle") first, then set event_loop.cycle_id on the returned dict — identical pattern to start_agent_span, start_model_invoke_span, and execute_tool spans.

Runtime proof on rebased branch 7eeab90:

• start_event_loop_cycle_span uses _get_common_attributes: True
• event_loop.cycle_id still set: True
• All 5 event-loop-cycle span tests: 5/5 PASSED
• Full telemetry suite: 74/74 PASSED

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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