Context

browsertrace doctor is now the first command in the README quickstart. New users may not know how to interpret its output, especially before they have created any local trace database.

Task

Add a short troubleshooting note to README.md or examples/README.md explaining the common browsertrace doctor states. Keep it concise and focused on first-run setup.

Suggested points to cover:

• Database: missing is expected before the first browsertrace demo run.
• Runs: 0 means the user should run browsertrace demo next.
• If UI dependencies are missing, use the existing GitHub-tag install path with [ui].
• Keep PyPI wording accurate: PyPI publishing is still pending until browsertrace is published.

Acceptance criteria

• The docs explain at least two common browsertrace doctor outputs.
• Existing uvx and GitHub-tag install commands stay on v0.1.12.
• The docs do not claim pip install browsertrace works before PyPI is published.
• Run uv run --python 3.11 --extra dev pytest -q before opening a PR.