Show and notify about GitHub PRs in the GitBook UI for git-synced spaces

[aldibit]

What's the feature/idea?

When a GitBook space is synced with a GitHub repository, contributors can open pull requests directly against the synced branch in GitHub. Currently, these PRs are completely invisible in the GitBook UI — there's no notification, no banner, no list of pending PRs, nothing. GitBook only shows Change Requests created natively inside its own UI.
I'd like GitBook to detect and surface GitHub PRs in its UI when a space is git-synced, so that:

• A notification or badge appears in the GitBook space when one or more open PRs exist against the synced branch on GitHub
• Team members with access to the space are notified (in-app and/or email) when a new PR is opened via GitHub
• The PR is listed alongside Change Requests in the GitBook UI, with a link back to GitHub to review/merge it OR an editable preview as native PRs

What's the desired outcome?

GitBook users should not need to monitor GitHub separately to know that a documentation PR is waiting for review. Today, PRs made via GitHub sync are effectively a blind spot. They don't trigger any signal inside GitBook, which means they can be missed by teams who primarily live in the GitBook UI.

Current behavior:

PRs opened against a git-synced branch in GitHub are ignored by the GitBook UI entirely.

Desired behavior:

GitBook polls or receives webhook events for open PRs on the synced branch, and surfaces them in the space UI. At minimum as a notification, ideally as first-class entries alongside Change Requests.

Why is this important?

Teams that use GitHub-first workflows (e.g., agents or developers opening PRs programmatically) have no visibility in GitBook unless they also check GitHub. Closing this gap would make the git sync integration truly bidirectional from a collaboration standpoint, not just in terms of content, but also in terms of review workflow awareness.

[ruthnwego]

+1! Our engineers frequently contribute to the documentation through GitHub, and it would be extremely helpful if these pull requests could be surfaced directly within the GitBook UI.