67f98b6bc5
The `aura new` scaffold shipped one node, a param-less Identity, so a downstream author had no public example of a build closure consuming a bound param — the highest-value gap the project-environment fieldtest found (F2): a newcomer could copy a param-less node but had to read engine source to write their first *tunable* one, which the consumer contract forbids. Swap that single starter node for a Scale node (mirroring the std gain operator): its schema declares a `factor` ParamSpec and its build closure reads the bound value (`|p| Box::new(Scale::new(p[0].f64()))`), and the starter blueprint binds `factor` so `aura run` exercises the bound-param path with zero hand-editing. factor is bound to 1.0 — a neutral identity default the newcomer then tunes, not the only C7-safe value (only |factor|>1 would push the terminal `bias` output past the bounded [-1,+1] contract; the knob is genuinely read and multiplied each cycle). The param-reading closure is the copyable template content #183 delivers; a hypothetical `|_|` regression is caught by the scaffold unit test's source guard, and tests/project_new.rs re-validates the swap by building and running the scaffold end to end. Template-side only (#181): the frozen 0102 demo-project fixture is untouched. closes #183