Developer ergonomics script — PR text

Problem / feature description

You are about to open a small pull request that adds a local helper script for engineers to regenerate protobuf stubs in one command. The change only affects the devtools/ folder; product management does not use a ticket for this yet—no Linear/Jira ID exists as of today. You still want a helpful PR body for teammates.

Write the GitHub pull request description (body only) to pr-body.md.

Output specification

Create exactly one file pr-body.md with the Markdown intended for the PR description field.