docs: add operations guide and docs updates

[jroth1111]

Supersedes #665. This PR keeps docs-only changes and consolidates routing examples in docs/operations.md; no config.example.yaml changes.

[jroth1111]

I created this PR from the wrong branch (it includes OAuth/auth changes). Closing it and opening a docs-only replacement shortly.

[gemini-code-assist]

Summary of Changes

Hello @jroth1111, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a comprehensive overhaul of the application's OAuth authentication infrastructure. The core objective is to create a more robust, maintainable, and user-friendly authentication experience by centralizing common OAuth patterns. This is achieved through the development of new oauthflow, oauthhttp, and refresher packages. The oauthflow package provides a standardized framework for handling both authorization code and device code grants, while oauthhttp ensures resilient communication with OAuth providers through automatic retries. The refresher worker proactively manages token lifecycles, refreshing them before expiry. These foundational changes are integrated across all supported OAuth providers, replacing previous disparate implementations with a unified and more reliable system.

Highlights

• Unified OAuth Flows: Centralized OAuth authorization code and device code flows into a new oauthflow package, standardizing authentication logic across all providers like Anthropic, Gemini, Codex, Antigravity, Qwen, and iFlow.
• Resilient HTTP Requests: Introduced an oauthhttp package that provides an HTTP client with automatic retry and exponential backoff for transient network errors, enhancing reliability of OAuth interactions.
• Proactive Token Management: Implemented a refresher background worker to automatically refresh OAuth tokens before they expire, minimizing service interruptions and improving user experience.
• Enhanced OAuth Status Tracking: Replaced ad-hoc OAuth session management with a thread-safe oauthStatus map and dedicated helper functions for robust tracking of authentication progress and errors.
• Improved Callback Server: Upgraded internal OAuth callback servers to dynamically bind to available ports and include URL validation for success page redirects, increasing flexibility and security.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This is an impressive and substantial refactoring of the authentication and OAuth flows. The introduction of the oauthflow, oauthhttp, and refresher packages provides a robust, reusable, and much cleaner abstraction for handling various authentication mechanisms. Centralizing the logic for OAuth flows, HTTP retries, and background token refreshing is a significant improvement for maintainability and correctness. The code is now more secure and less prone to bugs related to concurrency and resource management. I've included a couple of suggestions to reduce minor code duplication, but overall, this is excellent work.