fix(otel): End all recording spans on non-terminal invocations

[ayushiahjolia]

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Issue Link, if available

#624

Description

Ensures no recording span is ever left un-ended on a non-terminal (PENDING/RETRYING) invocation, which previously abandoned open Workflow and operation spans on every suspend.

• Workflow span (both plugins): No longer created in onInvocationStart. Between invocations it exists only as a deterministic SpanContext (stable trace and span ID) that operation and attempt spans link to. The recording span is started and ended in a single call on the terminal invocation only, parented onto the execution ancestor - so it is never left open.
• Operation spans (ExecutionOtelPlugin): Deferred. onOperationStart retains only a deterministic context; the span is created once in onOperationEnd (with a start-timestamp fallback for virtual map/parallel operations that report no timestamp at end), so a suspended operation never leaves an open span and a suspended-then-resumed operation still stitches into one logical span. InvocationOtelPlugin continues to create operation spans eagerly but force-ends any still open at invocation end.
• Attempt spans: Any still open at invocation end are force-ended.

Demo/Screenshots

N/A

Checklist

• I have filled out every section of the PR template
• I have thoroughly tested this change

Testing

Unit Tests

Have unit tests been written for these changes? Updated

Integration Tests

Have integration tests been written for these changes? N/A

Examples

Has a new example been added for the change? (if applicable) N/A

[ayushiahjolia]

/ai review

[ayushiahjolia]

/ai review

[ayushiahjolia]

/ai review

[github-actions]

Codex AI review

No actionable findings. Residual risk: lifecycle tracking is hook-level; no runner-level test verifies that PENDING/RETRYING executions leave no recording spans open.

Reviewed commit 1b92765dbcbf373801e69fbe875971587eac61d2. Workflow run