Update PR Workflow

Update an existing pull request using this flow.

1. •Gather branch and PR context:
   • •git rev-parse --abbrev-ref HEAD
   • •gh repo view --json defaultBranchRef -q .defaultBranchRef.name
   • •git status --short
   • •gh pr view --json number,url,title,body,baseRefName,headRefName,isDraft
   • •git log --oneline <base-branch>...HEAD
   • •git diff --stat <base-branch>...HEAD
   • •git diff <base-branch>...HEAD
2. •Handle missing PR:
   • •If gh pr view fails, explain no open PR exists for this branch
   • •Ask whether to switch to $create-pr or abort
3. •Handle uncommitted changes:
   • •If git status --short is not empty, ask whether to commit, ignore, or abort
   • •Do not continue until the user answers
4. •Load a PR template when available:
   • •git ls-files ':(top,icase).github/pull_request_template.md' ':(top,icase).github/pull_request_template/*.md' ':(top,icase)pull_request_template.md'
   • •Keep template heading order and HTML comments (<!-- -->) when filling sections
5. •Ask for updates to include:
   • •Confirm whether the title should change or stay as-is
   • •Ask for links to include (issues, docs, related PRs)
   • •Ask what changed since the last PR draft/review and highlight reviewer-facing impact
6. •Draft updated PR title and body:
   • •Title: Conventional Commits format, under 72 chars
   • •Decide title language before drafting and keep it fixed unless the user requests a change
   • •Title language policy: use template language first whenever it can be detected
   • •If the user explicitly asks to override language for the current PR, follow that override
   • •If no template language is detected, use: explicit user request > latest substantive user message > English
   • •Ignore command-style invocations (for example $update-pr), code blocks, file paths, and URLs when inferring language
   • •If language signals conflict or are ambiguous, ask the user which language to use before drafting
   • •Keep type(scope) tokens standard (for example feat, fix, chore); localize only descriptive text
   • •If no template exists, use sections: Summary / Changes / Concerns / References
7. •Confirm the final title and body with the user:
   • •Apply requested edits and re-confirm
   • •Do not push or edit the PR before approval
8. •Push and update:
   • •Push with git push -u origin HEAD when needed
   • •Update with gh pr edit <number> --title "<title>" --body-file <file>
   • •Return the PR URL