Brummel
3b496883e6
In the blueprint view's `where:` section, a composite's output re-exports now fold onto their producing node's label as a binding (`[macd := Sub(#Ef,#Es)]`) instead of each becoming a standalone terminal node wired from its producer. An OutField re-exports an existing interior node's value — it is never a new node — so the old form drew false terminals (MACD's macd line feeds the signal EMA and histogram internally yet rendered as a dead-end leaf) and inflated the node count by the output arity (MACD where: 8 -> 6 nodes; sma_cross drops its [cross] stub + edge). The drawn graph is now exactly the computation DAG; the `:=` prefix is the visual signal that a node's value escapes the boundary. Input roles stay standalone entry nodes (no producer to annotate) — the asymmetry is deliberate. render_definition drops its per-OutField node+edge loop; a new output_binding helper yields the `name := ` / tuple `(a, b) := ` prefix. Pure render layer: C8/C23 untouched, OutField.name never reaches the compilat, compiled_view_golden byte-identical, MACD run deterministic and unchanged in metrics. Test blast radius was wider than spec 0022 §Components / the plan's Scope note counted: besides the MACD pinning test, four more sites assert a producer that carries an OutField and so gain the `:=` prefix — blueprint_view_defines_each_composite_once, the two fan-in identifier tests, the cli_run integration test, and (missed by the plan, caught at implement) the full-render blueprint_view_golden. All re-pins are forced by the design, zero judgement. The output_binding tuple arm is unexercised by current fixtures (no composite re-exports >1 field from one node). Verified: cargo test --workspace 0 failed; clippy --all-targets -D warnings clean. closes #46