feat: add release plan approval workflow variables

[huanghongbo-hhb]

Summary

• Add workflow built-in variables to identify release plan triggered workflow tasks and whether the release plan approval has passed.

Why

• Release plans can already require approval before execution. Workflows triggered by an approved release plan need a reliable variable so approval jobs can be conditionally skipped without affecting normal workflow executions.

Main Changes

• Store release plan approval-pass state on the workflow task release plan reference.
• Expose workflow.task.from_release_plan and workflow.task.release_plan_approved as referable workflow runtime variables.
• Keep standalone workflow execution and release plans without approval on workflow.task.release_plan_approved=false so workflow approval jobs still run normally.

Risk / Compatibility

• Low compatibility risk: the change only adds optional fields/variables and does not automatically skip any job. Skipping still depends on workflow job execute policy configuration.
• Existing workflow task release plan references without approval_passed default to false.

Test

• go test ./pkg/microservice/aslan/core/workflow/service/workflow/controller
• GOCACHE=/private/tmp/zadig-gocache go test -vet=off ./pkg/microservice/aslan/core/workflow/service/workflow
• GOCACHE=/private/tmp/zadig-gocache go test -vet=off ./pkg/microservice/aslan/core/release_plan/service

Contact

• Contact: huanghongbo@koderover.com

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