Create Pr.Prompt

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Use the GitHub MCP server to create a pull request — do NOT use the gh CLI.

1. Run the compile and hygiene tasks (fixing any errors)
2. Review all changes in the current session
3. Write a clear, concise PR title with a short area prefix (e.g. "sessions: …", "editor: …")
4. Write a description covering what changed, why, and anything reviewers should know
5. Create the pull request