Register an agent that an agent created

[astetic-dev]

Part of the special agents work. A special agent is an ICM role — Architect,
Operator, Cartographer, Diagnostician, Editor, Researcher, Coach — deployed from a
source you point at, either standing in its own workspace or embedded in one work
process. Taurus itself contains no ICM technique; it holds a source per role, keeps
it current, and puts the contents where the work is.

Why

Three of the seven roles are factories. The Architect builds a work process, the
Coach builds a coach, the Operator builds an operator. Each leaves behind a
folder that is exactly what Taurus calls an agent — but Taurus does not know,
because it was not deployed and not cloned. It came into being inside a tab.

With one factory this is an edge case. With three it is a routine.

What

Three options were considered:

	how	cost
a	the user notices and presses ＋ → a folder you have	nothing, works today
b	the factory writes a small .taurus-agent.json in the new folder; Taurus notices it and offers to add it	an agreement the agent has to keep
c	Taurus watches the tab and works it out	fragile, and guesswork

b is the shape this should take, and it is achievable here in a way it would
not be for most applications: most of the role repositories are ours, so they can
be given that agreement. Build it once a role exists that honours it — not
before. Until then, a is the answer and costs nothing.

Proposed file, written by the factory into the folder it just created:

{ "label": "Ordersflow", "role": "", "task": "" }

Taurus offers; the user decides. Never register silently.

Depends on

#155, #159.

[astetic-dev]

Deliberately left open. Variant (a) works today: when a factory role leaves a folder behind you press the plus and pick it as a folder you already have. Variant (b) -- the role writes a small file and Taurus offers to register it -- waits until a role exists that honours the agreement, so we are not building a reader for something nobody writes.