Add GitHub traffic, release download, and adoption measurement checklist

[httpdss]

Summary

Add a lightweight measurement checklist so maintainers can evaluate whether relaunch, content, and community efforts are producing real adoption signals.

Scope

Create a markdown doc such as docs/visibility-metrics.md that tracks:

• GitHub stars, forks, watchers.
• GitHub traffic: views, clones, referrers.
• Release asset downloads, especially .deb packages.
• Docker pulls if a container is published later.
• Discussions/issues/PRs from non-maintainers.
• External mentions/backlinks.
• Python backend tester feedback count.

Why this matters

The goal is not just more stars — it is more users, testers, contributors, and successful installs.

Acceptance criteria

• Measurement doc exists and includes a simple weekly tracking table.
• Includes recommended UTM conventions for links from social/blog/community posts.
• Separates vanity metrics from adoption/contribution metrics.
• Maintainer-facing docs or README link to the checklist where appropriate.

[github-actions]

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