fix: lazy fill workflow task release plans

[huanghongbo-hhb]

Summary

• lazy fill release plan metadata for historical workflow task records in workflow history APIs

Why

• after the release plan column was enabled, historical workflow tasks still could not show their related release plans until a new release plan execution happened
• the existing direct workflow_task.release_plan field only covers tasks created after the feature landed

Main Changes

• add a release plan repository query that maps the current workflow and current page task IDs to release plan refs
• lazy fill missing release_plan data in workflow task list and detail APIs instead of waiting for a new execution
• asynchronously persist the resolved release plan ref back to workflow_task so later requests can hit the direct field

Risk / Compatibility

• low risk: this only affects workflow history release plan enrichment for tasks missing release_plan
• new tasks still use the existing direct write path; old tasks are enriched from existing release plan task associations

Test

• tests not run

Contact

• Contact: huanghongbo@koderover.com

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