Add second question (jaren werkzaam) to herregistratie wizard step 1

Step 1 was a single field, making the wizard feel thin. Add "Aantal jaren
werkzaam" beside "Gewerkte uren" on the same step (no new step): Draft/Valid
gain `jaren`, `next` validates both step-1 fields before advancing, and
`validate` parses it for the submitted payload. Verified live: an empty jaren
blocks advancing with an inline error.

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

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

@@ -4,12 +4,14 @@ import { Uren, parseUren } from '@registratie/domain/value-objects/uren';
 /** What the user is typing (raw, possibly invalid). */
 export interface Draft {
   uren: string;
+  jaren: string;
   punten: string;
 }
 
 /** What we have AFTER parsing — branded/typed, guaranteed valid. */
 export interface Valid {
   uren: Uren;
+  jaren: number;
   punten: number;
 }
 
@@ -25,26 +27,32 @@ export type WizardState =
   | { tag: 'Submitted'; data: Valid }
   | { tag: 'Failed'; data: Valid; error: string };
 
-export const initial: WizardState = { tag: 'Editing', step: 1, draft: { uren: '', punten: '' }, errors: {} };
+export const initial: WizardState = { tag: 'Editing', step: 1, draft: { uren: '', jaren: '', punten: '' }, errors: {} };
 
 /** Parse every field; on success hand back a Valid, else the per-field errors. */
 function validate(draft: Draft): Result<Partial<Record<keyof Draft, string>>, Valid> {
   const uren = parseUren(draft.uren);
+  const jaren = parseUren(draft.jaren);
   const punten = parseUren(draft.punten);
   const errors: Partial<Record<keyof Draft, string>> = {};
   if (!uren.ok) errors.uren = uren.error;
+  if (!jaren.ok) errors.jaren = jaren.error;
   if (!punten.ok) errors.punten = punten.error;
-  if (uren.ok && punten.ok) return { ok: true, value: { uren: uren.value, punten: punten.value } };
+  if (uren.ok && jaren.ok && punten.ok) {
+    return { ok: true, value: { uren: uren.value, jaren: jaren.value, punten: punten.value } };
+  }
   return { ok: false, error: errors };
 }
 
-/** Step 1 → 2: only advance if the uren field parses. Illegal elsewhere = no-op. */
+/** Step 1 → 2: advance only when BOTH step-1 fields parse. Illegal elsewhere = no-op. */
 export function next(s: WizardState): WizardState {
   if (s.tag !== 'Editing' || s.step !== 1) return s;
   const uren = parseUren(s.draft.uren);
-  return uren.ok
-    ? { ...s, step: 2, errors: {} }
-    : { ...s, errors: { uren: uren.error } };
+  const jaren = parseUren(s.draft.jaren);
+  const errors: Partial<Record<keyof Draft, string>> = {};
+  if (!uren.ok) errors.uren = uren.error;
+  if (!jaren.ok) errors.jaren = jaren.error;
+  return Object.keys(errors).length === 0 ? { ...s, step: 2, errors: {} } : { ...s, errors };
 }
 
 export function back(s: WizardState): WizardState {