orbistoun drives the session now, and D207 said it never would

orbistoun session <host:port> --out <file> connects to a listening probe, negotiates, runs what it announced, and writes the transcript. orbistoun probe <file> reads it back. The live path and the file path go through one parser, so they cannot drift into two different truths.

D207 said orbistoun was a responder and never a driver. That is reversed, and recorded as a reversal: machine identity must be operator-asserted, and the operator is sitting in front of orbistoun, not in front of a freestanding C probe with no interface.

What survives is the half that mattered. Client is generic over anything that reads and writes bytes, so all nine of its tests drive it from memory and CI never opens a socket. connect() is the only function that knows a socket exists.

Surprises

Every interesting test is a failure path, and none of them is reachable against real hardware. Acknowledged-then-cut-off is a death; closed-before-acknowledgement is lost rather than a death, because without an acknowledgement nothing establishes the command ran at all; silence within the budget is a timeout and deliberately not resolved into either. A client exercised only against a working console would have none of these tested, and they are the normal case rather than the exceptional one.

The capability check belongs on the client side, and that is not obvious. Refusing to send an un-announced verb looks like duplicated validation - the probe will refuse it anyway. But a client that waits to be refused has already put a command on the wire that this probe does not implement, and on a target that faults easily that is not free. The test asserts the wire stayed clean, not merely that an error came back.

A doc comment merged into its neighbour for the third time today. Inserting an enum variant before Probe { put it between Probe's doc comment and Probe, so --help printed three commands' prose under one. Fixing that pushed the same collision one variant further up into Shaders. The rule earned twice over now: anchor on the item line, never on the prose above it.