Adds two new documentation pages under platform controls for Coder
Agents:
- **Git Providers** (`git-providers.md`) — documents the `API_BASE_URL`
configuration required for self-hosted GitHub Enterprise deployments.
Positions it as an extension of the existing [external
auth](https://coder.com/docs/admin/external-auth) setup to support Coder
Agents features that need richer git host API access: the in-chat diff
viewer and PR Insights.
- **PR Insights** (`pr-insights.md`) — documents the PR analytics
dashboard, requirements for PR data to appear, and troubleshooting.
Links to git-providers for GHE setup.
Also updates the platform controls index and docs manifest.
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> PR generated with Coder Agents
