Step 1: i18n foundation (@angular/localize) + data inventory

Domain reference data already lives in the backend (per ADR-0001); the only
residual "move" was ~90 inlined Dutch UI strings with no i18n layer.

- Wire @angular/localize ($localize) — Angular first-party, no third-party lib
- Pin the pattern on shared/ui/async: Dutch fallbacks → language-agnostic
  input()s with localizable $localize defaults (English-shared-UI rule)
- CLAUDE.md: drop i18n (now in scope) + stale "real backend"/"OpenAPI codegen"
  (both already shipped); document the $localize convention

Bulk string sweep deferred to Step 2 to avoid touching ~36 files twice.

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

CLAUDE.md

@@ -122,6 +122,13 @@ not heavy component tests.
 - **Naming:** shared/reusable UI is **English** (language-agnostic: `button`,
   `wizard-shell`); domain contexts are **Dutch** (`registratie`, `herregistratie`,
   `*.machine.ts`). Pick the language by which side of the seam the code is on.
+- **User-facing copy = `$localize`.** Every user-visible string is wrapped in Angular's
+  first-party `$localize` (no third-party i18n lib), with a stable custom id
+  (`` $localize`:@@context.key:Tekst` ``). Source locale is `nl`; a second locale is a
+  translation file, not a code change (the seam). Shared/English components must **not**
+  hardcode Dutch — expose copy as `input()`s with localizable defaults; the domain caller
+  supplies the text (see `shared/ui/async`). Format-validation messages in
+  `domain/value-objects/` stay co-located but are still `$localize`-wrapped.
 - **Forms = one idiom.** Any form with validation or submission uses a `*.machine.ts`
   (Model/Msg/reduce) + value objects + a `submit-*` command returning `Result` — the
   same shape as the wizards, whether it's one step or many. Don't hand-roll mutable
@@ -148,5 +155,5 @@ dispatch messages). Worked example: the intake wizard (`herregistratie/`).
 
 ## Out of scope (POC, don't build unprompted)
 
-Real auth/DigiD, real backend, i18n, NgRx, licensed Rijkshuisstijl font/logo,
-runtime DTO validation on every endpoint, multi-tab session sync, OpenAPI codegen.
+Real auth/DigiD, NgRx, licensed Rijkshuisstijl font/logo,
+runtime DTO validation on every endpoint, multi-tab session sync.