Graphite Q1 launch week: Making stacking seamless

Graphite's Q1 launch week introduces new features to enhance the process of stacking pull requests (PRs) on GitHub, addressing the challenges of managing stacked changes and upstream modifications. Key features include Stack Edit, which allows users to apply consistent labels, reviewers, and settings across all PRs in a stack, and Stack Visualization, which provides a clear overview of PRs and their statuses. An interactive terminal tutorial, gt demo, guides users through creating and managing stacks, while AI-generated stack titles offer high-level context for reviewers. These features aim to streamline and automate the manual tasks associated with stacked diffs, making the review process more efficient and accessible.