kaivo doctor: find what's wrong

When something gets stuck, run kaivo doctor before anything else. It checks, point by point: which kaivo program runs and whether another one comes before it in your PATH, whether you're signed in with a valid session, whether the Kaivo site answers, and which optional tools are installed (git, ripgrep, fzf, language servers).

Each line starts with a tick (all good), an exclamation mark (optional or worth watching) or a cross (a real problem, with how to fix it). If you write to support, just paste the result: we'll see the essentials right away.