Add target field support to add-labels safe output

[Copilot]

Fixes issue where the target field was not supported for add-labels safe output, unlike add-comment which already had this functionality.

Problem

The add-labels safe output configuration was missing support for the target field, which meant labels could only be added to the triggering issue/PR. The Go code already parsed and passed the target configuration via environment variables, but the JavaScript/TypeScript implementation didn't consume it.

Solution

This PR completes the implementation by adding target field support to the JavaScript/TypeScript code, bringing add-labels to feature parity with add-comment.

The target field now supports three modes:

• "triggering" (default): Adds labels to the triggering issue/PR
• "*": Allows adding labels to any issue by specifying issue_number in the agent output
• Explicit number (e.g., "123"): Adds labels to a specific issue number

Usage Example

safe-outputs:
  add-labels:
    allowed: [bug, enhancement, documentation]
    target: "*"

With this configuration, the agent can add labels to multiple issues in a single workflow run by including issue_number in the output:

# Issue Labeling Agent

Add the label "bug" to issue #1 and the label "documentation" to issue #2.

Changes

• Updated pkg/workflow/js/add_labels.ts to read and use GITHUB_AW_LABELS_TARGET environment variable
• Implemented target handling logic consistent with add-comment implementation
• Added 8 comprehensive tests covering all target scenarios
• Updated documentation in docs/src/content/docs/reference/safe-outputs.md
• Created example test workflow demonstrating the feature

Testing

All tests pass including:

• 43 tests in the add_labels test suite
• Full unit test suite
• Linting and TypeScript compilation
• Example workflow compilation

Original prompt

---

This section details on the original issue you should resolve

<issue_title>add-labels target not supported</issue_title>
<issue_description>Similar to add-comment, add-labels should support target field</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #1099

---

💬 Share your feedback on Copilot coding agent for the chance to win a $200 gift card! Click here to start the survey.