Create the feature's data/ layer (pure spec; depends on nothing but @adobe/data
and other data/ declarations):
- one namespace folder per data type —
<type>/{<type>.ts, schema.ts, public.ts, <helper>.ts}; data/state/— theStateaggregate plus its pure transforms/derivations.
The schema is the single source of truth; the type derives from it (Schema.ToType).
Helpers are pure and unit-tested. Run this first — every other layer imports data/.
The how is in the auto-loading rules: features/data/index.md, data/state.md, and
namespace.md.