feat(dx): WP-43 — plop generators (value-object, form-machine)

Runnable `npm run gen:value-object` / `gen:form-machine` (plop) that scaffold the two
pure-TS house patterns with a co-located spec: a branded value object + parseX (mirrors
postcode/bsn), and an Elm-style form/wizard machine (Draft/Valid/Errors + Editing/
Submitting/Submitted/Failed union + initial/pure reduce/assertNever). Prompts take
context + PascalCase name (positional-arg bypass); a post-action reminds to add the
English target for the generated $localize id. Templates in plop-templates/ (prettier-
ignored). Skills (value-object, form-machine) point at the generators. ui-component +
bff-endpoint stay skill-driven (Angular {{}} / backend + gen:api).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.claude/skills/value-object/SKILL.md

@@ -8,6 +8,10 @@ description: Add a validated input type (postcode, email, hours, id number, …)
 Raw input becomes a branded type only via a parser returning `Result`. Once you hold
 the type, never re-check it. Never model validity as a boolean flag next to a string.
 
+**Scaffold it:** `npm run gen:value-object` (WP-43) emits the branded type + `parseX` + spec
+into `<context>/domain/value-objects/`. Then fill in the real format rule and add the English
+`<target>` for the generated `@@validation.<name>` id (the localize gate).
+
 ## Skeleton
 
 `<context>/domain/value-objects/<name>.ts` (pure TS, no Angular):