Support bot identity for automated PR reviews

[omriariav]

Problem

When using Claude Code sub-agents to review PRs, comments are posted under the developer's own GitHub account. This makes it hard to distinguish human feedback from automated review feedback.

Desired Behavior

Support posting PR review comments (summary + inline) under a separate GitHub identity (bot account or GitHub App) so that automated reviews are clearly distinguishable from human reviews.

Proposed Approach

• Accept a configurable GH_REVIEW_BOT_TOKEN environment variable
• When set, PR review agents use this token (GH_TOKEN=<token> gh pr ...) instead of the default gh auth
• Comments then appear under the bot's identity (e.g. code-review-bot[bot])

Options

1. GitHub App — cleanest; shows as app-name[bot], fine-grained permissions
2. Separate PAT — simpler setup; requires a second GitHub account
3. Configurable in settings — add a review-bot-token field to project settings

Context

Currently PR review sub-agents are spawned manually during Claude Code sessions. Adding bot identity support would improve review UX and enable future automation via GitHub Actions.