authoring

The authoring layer that lowers to the pure node IR.

@cg.procedure (in compiled), the recording contexts (sequence, set, optional, conditional, loop, detached, and the root context they reduce into), the steps helpers (cg.do / cg.do_optional), the dispatch that resolves a navigation into the right node, the per-slot paths state, the errors, and the value bridge that coerces authored values into nodes. All of it is a thin surface over capturegraph.procedures — never a new node kind, and with no global state: constructing a node registers it with the active context, which reduces the body to its roots. The single authoring surface is the capturegraph root (import capturegraph as cg).