Mijn aanvragen (E): two-flow submit through the aanvraag + all-wizard persistence

All three wizards now submit through the backend aanvraag lifecycle, so a
submitted Concept actually transitions (dashboard shows it correctly in F).

- blockActions(status) (domain + spec): the pure per-status action decision
  (Concept → resume/cancel; In behandeling → viewDocuments; resolved → none).
- createDraftSync.submit(): ensure the Concept exists, then
  POST /applications/{id}/submit; folded into a Result like the old commands.
- registratie: submit via draftSync (duo → auto, handmatig → manual pending — the
  old 422 path is gone from the wizard).
- intake + herregistratie: adopt createDraftSync (persistence + resume-by-link);
  intake retires sessionStorage `intake-v3`; herregistratie gains persistence.
  Both submit through the aanvraag too. hasProgress added to each machine (+spec).
- Delete now-dead submit-registratie/submit-intake/submit-herregistratie commands.

Deferred: the old /registrations, /intakes, /herregistraties backend endpoints +
RejectRegistratie are now unused by the FE but still present (+ tested) — retiring
them cascades into backend test rewrites, so it's a focused follow-up cleanup.
Gates green: vitest 128, lint, build; backend unchanged (dotnet 56).

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

src/app/herregistratie/domain/intake.machine.ts

@@ -68,6 +68,12 @@ export function currentStep(s: Extract<IntakeState, { tag: 'Answering' }>): Step
   return STEPS[Math.min(s.cursor, STEPS.length - 1)];
 }
 
+/** Has the user meaningfully started, so it's worth persisting as a Concept?
+    (No auto-prefill here — pristine means truly untouched.) */
+export function hasProgress(s: Extract<IntakeState, { tag: 'Answering' }>): boolean {
+  return s.cursor > 0 || Object.keys(s.answers).length > 0;
+}
+
 /** Validate every question currently visible in ONE step. Errors keyed per field. */
 function validateStep(step: StepId, a: Answers, scholingThreshold: number): Result<Errors, void> {
   const errors: Errors = {};