- backend: dotnet format the WP-51 migration (2-space indent, no BOM) to match .editorconfig — dotnet format --verify-no-changes was failing. - storybook: stub FeatureFlagStore (WP-47) in shell/site-header stories alongside AccessStore, fixing NG0201 no-provider errors; bump the storybook-a11y container's memory cap 4g→6g (build-storybook + compodoc measured ~5.8GB peak RSS, leaving too little headroom). - backend: fix a startup-breaking bug in the new (WP-52) POST /zgw/notificaties handler — it took ZgwOptions as a minimal-API parameter, which isn't registered in DI, so ASP.NET's endpoint-table build threw on every request once the route was registered (incl. /swagger, which is why Playwright's webServer health check timed out). Close over the existing `zgw` local instead. - e2e: brief-v2.spec.ts's "Voorbeeld" button locator was ambiguous once a second "Voorbeeld met testwaarden" button existed (Playwright name matching is substring-based) — added `exact: true`. Also fixed the sent-letter preview flow to match app-letter-composer's actual behavior (single click → fetch, no in-page dialog, unlike app-behandel-scherm's), and fixed a watermark assertion that checked for the always-present `.preview-watermark` CSS class name instead of the conditionally-rendered "VOORBEELD" marker text. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>