fix: allow adding required reviewers in update_reviewers

[Vasilii Boldurean (boldurean)]

repo_pull_request_write with action: "update_reviewers" always added reviewers as optional. There was no way to add a required reviewer, which is the normal case for teams whose branch policy expects named required reviewers.

This PR adds an optional isRequired boolean input:

• When reviewerAction is add, it is passed through to createPullRequestReviewers as { id, isRequired } for each reviewer.
• When omitted, the payload is { id } as before, so existing behaviour is unchanged.
• The trimmed response now includes isRequired for each reviewer, so callers can confirm the result.

Example:

{
  "action": "update_reviewers",
  "reviewerAction": "add",
  "isRequired": true,
  "repositoryId": "<repo>",
  "pullRequestId": 123,
  "reviewerIds": ["<identity id>"]
}

GitHub issue number

None filed.

Associated Risks

Low. The new input is optional and the request payload is identical to before when it is omitted. Not yet confirmed: whether re-adding an existing optional reviewer with isRequired: true promotes them to required through the batch endpoint.

✅ PR Checklist

• I have read the contribution guidelines
• I have read the code of conduct guidelines
• Title of the pull request is clear and informative.
• 👌 Code hygiene
• 🔭 Telemetry added, updated, or N/A
• 📄 Documentation added, updated, or N/A
• 🛡️ Automated tests added, or N/A

🧪 How did you test it?

• Added a unit test that checks isRequired: true is sent for every reviewer and returned in the response.
• Existing update_reviewers test still passes with the unchanged { id } payload.
• jest test/src/tools/repositories.test.ts: 331 passed, 100% coverage on repositories.ts.
• tsc, prettier --check and eslint are clean.

[Vasilii Boldurean (boldurean)]

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[Dan Hellem (danhellem)]

We are closing this issue per contribution guidelines. Please create an Issue first and have it reviewed before creating a PR

[Vasilii Boldurean (boldurean)]

We are closing this issue per contribution guidelines. Please create an Issue first and have it reviewed before creating a PR

Hi Dan Hellem (@danhellem), sorry missed that, will do so thanks

[Vasilii Boldurean (boldurean)]

Dan Hellem (@danhellem) just seen the issue was already raised in discussions - #899 (comment)