chore: publish — flip public, mark template, topics, portfolio polish (badges, screenshots)

[constk]

Problem

Until the repo is public, marked as a template, and discoverable via topics, it isn't a portfolio piece — it's a private folder.

Proposed solution

Flip repo visibility to public (gh repo edit --visibility public). Mark as template (gh repo edit --template). Apply branch-protection JSON via branch-protection.yml workflow_dispatch. Add topics: template, python, fastapi, react, vite, typescript, claude-code, llm-coding, harness, pre-commit, opentelemetry. Add screenshots/GIFs to README (green CI, hello page, Jaeger trace, just check run). Pin to the GitHub profile.

Acceptance criteria

• Repo public; template flag visible ("Use this template" button works).
• Topics applied; repo discoverable via topic search.
• Branch protection applied to main and develop.
• Screenshots/GIFs in README render correctly on github.com.
• Pinned to profile.

Priority rationale

Medium: the work is done by ticket #27; this ticket just flips the switches that make it a portfolio piece.

Depends on

#27