test(frontend): replay real messages instead of hand-built state literals (WP-70)

Every machine spec redefined its own throwaway fixture helper (editing1/2/3,
editingWith), hardcoding fields like errors: {} that assert against shapes
the reducer may never actually produce. given(reduce, initial)(...msgs)
(libs/shared/src/testing/machine.ts) replaces them by replaying real Msgs
through the real reduce, so a fixture is provably reachable. Adds the same
idiom for value objects (unwrapOk) and RemoteData (loading/success/failure),
plus intake.acceptance.spec.ts as a worked full-journey example.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/ssp/src/app/herregistratie/domain/herregistratie.machine.spec.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect } from 'vitest';
 import { ok, err } from '@shared/kernel/fp';
-import { initialUpload } from '@shared/upload/upload.machine';
+import { given } from '@shared/testing/machine';
 import {
   initial,
   next,
@@ -12,74 +12,80 @@ import {
   WizardState,
 } from './herregistratie.machine';
 
-const editing1 = (uren: string, jaren = '5', punten = ''): WizardState => ({
-  tag: 'Editing',
-  step: 1,
-  draft: { uren, jaren, punten },
-  errors: {},
-  upload: initialUpload,
-});
-const editing2 = (uren: string, punten: string, jaren = '5'): WizardState => ({
-  tag: 'Editing',
-  step: 2,
-  draft: { uren, jaren, punten },
-  errors: {},
-  upload: initialUpload,
-});
-const editing3 = (uren: string, punten: string, jaren = '5'): WizardState => ({
-  tag: 'Editing',
-  step: 3,
-  draft: { uren, jaren, punten },
-  errors: {},
-  upload: initialUpload,
-});
+const wizard = given(reduce, initial);
+
+/** Replay to a step-1 Editing state with the given draft values — the ONLY
+    door to a WizardState is `reduce`, so a fixture here is provably reachable. */
+const toStep1 = (uren: string, jaren = '5'): WizardState =>
+  wizard(
+    { tag: 'SetField', key: 'uren', value: uren },
+    { tag: 'SetField', key: 'jaren', value: jaren },
+  );
+
+/** Replay to a step-2 Editing state: reach step 1, advance, then set punten
+    (which may itself be invalid — Next only gated step 1's own fields). */
+const toStep2 = (uren: string, punten: string, jaren = '5'): WizardState =>
+  given(reduce, toStep1(uren, jaren))(
+    { tag: 'Next' },
+    { tag: 'SetField', key: 'punten', value: punten },
+  );
+
+/** Replay to a step-3 Editing state: reach step 2 with a placeholder-valid
+    punten so `Next` actually advances, THEN overwrite punten with the real
+    (possibly invalid) value — exactly what a user editing step 3 can do,
+    since `SetField` never re-checks the step it's setting a field for. */
+const toStep3 = (uren: string, punten: string, jaren = '5'): WizardState =>
+  given(reduce, toStep2(uren, '1', jaren))(
+    { tag: 'Next' },
+    { tag: 'SetField', key: 'punten', value: punten },
+  );
 
 describe('wizard.machine', () => {
   it('next advances only when step 1 parses', () => {
     expect(next(initial).tag).toBe('Editing'); // empty uren -> stays, with error
     expect((next(initial) as any).errors.uren).toBeTruthy();
-    expect((next(editing1('4160')) as any).step).toBe(2);
+    expect((next(toStep1('4160')) as any).step).toBe(2);
   });
 
   it('next advances step 2 → 3 only when punten parses', () => {
-    expect((next(editing2('4160', 'x')) as any).step).toBe(2); // invalid punten -> stays
-    expect((next(editing2('4160', 'x')) as any).errors.punten).toBeTruthy();
-    expect((next(editing2('4160', '200')) as any).step).toBe(3);
+    expect((next(toStep2('4160', 'x')) as any).step).toBe(2); // invalid punten -> stays
+    expect((next(toStep2('4160', 'x')) as any).errors.punten).toBeTruthy();
+    expect((next(toStep2('4160', '200')) as any).step).toBe(3);
   });
 
   it('submit reaches Submitting ONLY from step 3 with fully valid data', () => {
-    expect(submit(editing2('4160', '200')).tag).toBe('Editing'); // not on step 3 -> no Submitting
-    expect(submit(editing3('4160', 'x')).tag).toBe('Editing'); // invalid punten
-    const good = submit(editing3('4160', '200'));
+    expect(submit(toStep2('4160', '200')).tag).toBe('Editing'); // not on step 3 -> no Submitting
+    expect(submit(toStep3('4160', 'x')).tag).toBe('Editing'); // invalid punten
+    const good = submit(toStep3('4160', '200'));
     expect(good.tag).toBe('Submitting');
     expect((good as any).data).toEqual({ uren: 4160, jaren: 5, punten: 200, documents: [] });
   });
 
   it('next requires BOTH step-1 fields (uren and jaren)', () => {
-    expect((next(editing1('4160', '')) as any).errors.jaren).toBeTruthy(); // jaren empty -> stays
-    expect((next(editing1('4160', '')) as any).step).toBe(1);
-    expect((next(editing1('4160', '5')) as any).step).toBe(2); // both valid -> advance
+    expect((next(toStep1('4160', '')) as any).errors.jaren).toBeTruthy(); // jaren empty -> stays
+    expect((next(toStep1('4160', '')) as any).step).toBe(1);
+    expect((next(toStep1('4160', '5')) as any).step).toBe(2); // both valid -> advance
   });
 
   it('back steps down one (3 → 2 → 1) and is a no-op from step 1', () => {
     expect(back(initial)).toBe(initial); // step 1, nothing to go back to
-    expect((back(editing3('1', '2')) as any).step).toBe(2);
-    expect((back(editing2('1', '2')) as any).step).toBe(1);
+    expect((back(toStep3('1', '2')) as any).step).toBe(2);
+    expect((back(toStep2('1', '2')) as any).step).toBe(1);
     expect(resolve(initial, ok(undefined))).toBe(initial); // not Submitting
   });
 
   it('resolve maps Submitting to Submitted / Failed', () => {
-    const submitting = submit(editing3('4160', '200'));
+    const submitting = submit(toStep3('4160', '200'));
     expect(resolve(submitting, ok(undefined)).tag).toBe('Submitted');
     expect(resolve(submitting, err('boom')).tag).toBe('Failed');
   });
 
   it('gaNaarStap jumps back to an earlier step, clearing errors', () => {
-    expect((gaNaarStap(editing3('4160', '200'), 1) as any).step).toBe(1);
+    expect((gaNaarStap(toStep3('4160', '200'), 1) as any).step).toBe(1);
   });
 
   it('gaNaarStap ignores a same/forward jump and jumps outside Editing', () => {
-    const e3 = editing3('4160', '200');
+    const e3 = toStep3('4160', '200');
     expect(gaNaarStap(e3, 3)).toBe(e3); // same step -> no-op
     const submitting = submit(e3);
     expect(gaNaarStap(submitting, 1)).toBe(submitting); // not Editing -> no-op
@@ -113,7 +119,7 @@ describe('reduce (message-driven)', () => {
       multiple: false,
       allowPostDelivery: true,
     };
-    let s = reduce(editing3('4160', '200'), {
+    let s = reduce(toStep3('4160', '200'), {
       tag: 'Upload',
       msg: { type: 'CategoriesLoaded', categories: [cat] },
     });
@@ -130,7 +136,7 @@ describe('reduce (message-driven)', () => {
   });
 
   it('SubmitFailed then Retry returns to Submitting with the same data', () => {
-    let s = reduce(reduce(editing3('4160', '200'), { tag: 'Submit' }), {
+    let s = reduce(reduce(toStep3('4160', '200'), { tag: 'Submit' }), {
       tag: 'SubmitFailed',
       error: 'boom',
     });
@@ -141,6 +147,6 @@ describe('reduce (message-driven)', () => {
   });
 
   it('Seed mounts an arbitrary state', () => {
-    expect(reduce(initial, { tag: 'Seed', state: editing2('1', '2') }).tag).toBe('Editing');
+    expect(reduce(initial, { tag: 'Seed', state: toStep2('1', '2') }).tag).toBe('Editing');
   });
 });