Harden fork PR auto-close workflow and align contributor guidance

[Copilot]

At the moment we are not accepting contributions to the repository.

The workflow review requested tighter fork-PR handling and clearer contributor messaging. This update keeps behavior focused on fork PR auto-closure while reducing permission scope and documenting the policy link used in the close comment.

• Workflow scope and triggers (.github/workflows/auto-close-pr.yml)

  • Added synchronize to pull_request_target event types.
  • Removed unnecessary issues: write permission.
  • Moved fork/open/already-labeled checks to job-level if for clearer execution gating.
  • Removed author_association == 'NONE' restriction so all fork PRs are handled consistently.
  • Added explicit PR_NUMBER presence check before running gh commands.

• Contributor guidance in close comment

  • Extended the close message with a direct repository policy link:
    • https://github.com/github/CopilotForXcode#contributing-feedback
  • Retained Copilot community discussion link for feedback routing.

• Documentation alignment (README.md)

  • Added Contributing Feedback section to match workflow messaging and provide a stable reference target.

on:
  pull_request_target:
    types: [opened, reopened, synchronize]

permissions:
  pull-requests: write

jobs:
  close:
    if: >-
      github.event.pull_request.head.repo.full_name != github.repository &&
      github.event.pull_request.state == 'open' &&
      !contains(github.event.pull_request.labels.*.name, 'auto-closed')

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[Copilot]

Pull request overview

This PR tightens the repository’s fork PR auto-closure behavior and aligns contributor-facing messaging by linking to a stable “Contributing Feedback” section in the README.

Changes:

• Updates the auto-close workflow to also run on pull_request_target.synchronize, simplifies gating via a job-level if, and removes the author_association restriction.
• Extends the auto-close comment with a direct link to the repository’s contribution/feedback policy section.
• Adds a “Contributing Feedback” section in README.md to serve as the stable reference target.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
.github/workflows/auto-close-pr.yml	Expands trigger coverage and adjusts gating/permissions while updating the close message to include a policy link.
README.md	Adds a “Contributing Feedback” section intended to match the workflow’s guidance and provide a stable anchor link.

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[Copilot]

The new README section routes feedback exclusively to Discussions, but the auto-close workflow message now says the project accepts "issues and discussions". To keep contributor guidance consistent (and keep the README anchor link accurate), update this section to match the workflow message (or update the workflow message to match the README).

Suggested change

	questions, and bug reports through the [Copilot community
	questions, and bug reports through GitHub issues or the [Copilot community

[Copilot]

The workflow still creates labels and adds a label to the PR (and posts a PR comment via gh pr close --comment), which uses the Issues API. With issues: write removed, these gh label create, gh pr edit --add-label, and the close comment are likely to fail with permission errors. Either add issues: write back, or adjust the workflow to avoid label/comment operations that require it.

Suggested change

	pull-requests: write
	pull-requests: write
	issues: write