berth v0.1.8

First-run fix. What a user sees who installed from npm and never cloned the repository.

Fixed

• First run after npm install -g no longer points at a file the package does not contain. berth check, berth doctor and the SessionStart context text named examples/policy.example.toml, which ships only in the git repository, and none of them named berth init — the command that writes the policy and needs no files at all. All three now say berth init, and doctor's Claude rules row links the documentation site rather than examples/CLAUDE.ports.md. A test asserts no file under src/ cites a repository path again (#37).