Preserve issue_comment triggers in Depot CI migration

[PedroGuerraPT]

Change

• Mark issue_comment as supported in CLI compatibility rules.
• Preserve created, edited, and deleted activity filters when transforming workflows.
• Add compatibility and transform regression cases.

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Note

Low Risk
Compatibility metadata and test coverage only; migration behavior broadens to retain an additional trigger type with no auth or data-path changes.

Overview
Treats the GitHub Actions issue_comment trigger as supported for Depot CI migration instead of flagging it and stripping it during transform.

TriggerRules now marks issue_comment as Supported (with updated compatibility text and no removal suggestion). Workflows that run on issue/PR conversation comments should keep the trigger and types filters (e.g. created, edited, deleted) when migrated, rather than recording ChangeTriggerRemoved.

Regression tests cover compatibility analysis, the supported-trigger list, and transform output for an issue_comment workflow.

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[cursor]

Risk: low. Approved based on passing Cursor Bugbot and Cursor Security Agent checks with no findings that need human review. No reviewers were assigned.

  

_{Sent by Cursor Approval Agent: Pull Request Router and Approver}

[linear-code]

DEP-6961