Four-task plan executing spec 0019, sequenced like cycle 0018 (type-shape
change rippling engine -> CLI):
- T1 engine type migration, behaviour-preserving: Role/ParamAlias types,
Composite struct/new/accessors, inline_composite role-walk, lib.rs
re-export, all engine test Composite::new sites. Gate per-crate
(cargo test -p aura-engine, NOT --workspace; aura-cli compiles in T3).
The new params field is dormant -> param_space byte-identical, C23
anchor goldens green.
- T2 param aliasing RED-first: collect_params alias relabel + inline_composite
alias range-validation (-> BadInteriorIndex, reusing the variant), with
4 new unit tests (relabel, out-of-range, unaliased regression, partial).
- T3 CLI: render_definition [in:name]/[param:name] markers; MACD author
site (named role + fast/slow/signal aliases, the worked example);
sma_cross named role only; blueprint_view_golden re-capture;
compiled_view_golden stays byte-identical (C23 guard).
- T4 fieldtests sweep (separate workspace root -> explicit cargo build
gate, guarding the #42 latent-drift recurrence) + full --workspace
triple (-D warnings).
Aliasing demonstrated on the CLI MACD site only (the spec's evidence);
every other composite site gets the forced role-name + empty params, so
the param_space C23 anchor goldens stay byte-identical.
refs #41
