Architecture decisions

The decisions that shaped this project, and — more usefully — the reasoning that would have to change for them to be revisited.

They exist because the questions keep coming back. "Why SSH and not an agent?" is a fair question, it has a real answer, and that answer should not have to be reconstructed from scratch every time someone asks. Each record states what was decided, what it cost, and what would overturn it. A decision with no stated cost is a decision nobody examined.

These are records, not documentation: they describe the reasoning at a point in time. When one is superseded, it gets marked superseded rather than edited — a record that quietly changes to match the present teaches nothing.