Stundenplan Phase 3d: all 15 constraint editors via shared shell

Backend was already complete in Phase 2; this finishes the UI.

  - regeln/_shell.tsx introduces useConstraintCrud (handles list/create/
    delete state + reload), ConstraintShell (header, prereq banner,
    form toggle, error display, empty/loading/table render), and
    useShellStyles for the recurring theme tokens. Each editor now
    only carries its schema-specific bits.
  - Existing 4 editors (TeacherUnavailableDay/Window, SubjectMax
    Consecutive/PreferredPeriod) refactored onto the shell — every
    Playwright selector preserved.
  - 11 new editors covering the remaining constraint tables:
      TeacherMaxHours{Day,Week}, TeacherExcluded{Subject,Room},
      Subject{MinDayGap,ContiguousWhenRepeated,DoubleLesson},
      Class{MaxHoursDay,NoGaps},
      Room{RequiresType,Unavailable}.
  - RegelnHub now references all 15 editors directly — no more 'soon'
    placeholders. The two duplicate 'Max. Stunden / Tag' entries
    (teacher + class) are intentional and disambiguated by group.

Tests:
  - e2e/stundenplan.spec.ts: mock routes added for all 11 new constraint
    endpoints. RegelnHub suite gains a single test that switches
    through 13 uniquely-labelled editors, plus a dedicated test for
    the two duplicate 'Max. Stunden / Tag' labels.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

studio-v2/e2e/stundenplan.spec.ts

@@ -78,8 +78,19 @@ async function mockSchoolApi(page: Page, opts: MockOpts = {}) {
   for (const path of [
     'constraints/teacher/unavailable-day',
     'constraints/teacher/unavailable-window',
+    'constraints/teacher/max-hours-day',
+    'constraints/teacher/max-hours-week',
+    'constraints/teacher/excluded-subject',
+    'constraints/teacher/excluded-room',
     'constraints/subject/max-consecutive',
     'constraints/subject/preferred-period',
+    'constraints/subject/min-day-gap',
+    'constraints/subject/contiguous-when-repeated',
+    'constraints/subject/double-lesson',
+    'constraints/class/max-hours-day',
+    'constraints/class/no-gaps',
+    'constraints/room/requires-type',
+    'constraints/room/unavailable',
   ]) {
     await staticList(path, [])
   }
@@ -314,10 +325,37 @@ test.describe('Stundenplan — Regeln Hub', () => {
     await expect(page.getByTestId('subject-preferred-period-editor')).toBeVisible()
   })
 
-  test('unimplemented rules are disabled in the sidebar', async ({ page }) => {
-    const soonBtn = page.getByRole('button', { name: /Min\. Tagesabstand/ })
-    await expect(soonBtn).toBeDisabled()
-    await expect(page.getByText('soon').first()).toBeVisible()
+  test('all unique-labelled constraint editors mount when selected', async ({ page }) => {
+    // Skip 'Max. Stunden / Tag' (teacher + class both use it) — covered separately below.
+    const cases: { label: string; testId: string }[] = [
+      { label: 'Tag nicht verfuegbar', testId: 'teacher-unavailable-day-editor' },
+      { label: 'Zeitfenster nicht verfuegbar', testId: 'teacher-unavailable-window-editor' },
+      { label: 'Max. Stunden / Woche', testId: 'teacher-max-hours-week-editor' },
+      { label: 'Fach ausgeschlossen', testId: 'teacher-excluded-subject-editor' },
+      { label: 'Raum ausgeschlossen', testId: 'teacher-excluded-room-editor' },
+      { label: 'Max. Stunden am Stueck', testId: 'subject-max-consecutive-editor' },
+      { label: 'Bevorzugter Stunden-Bereich', testId: 'subject-preferred-period-editor' },
+      { label: 'Min. Tagesabstand', testId: 'subject-min-day-gap-editor' },
+      { label: 'Bei Mehrfach: zusammenhaengend', testId: 'subject-contiguous-when-repeated-editor' },
+      { label: 'Doppelstunde bevorzugt', testId: 'subject-double-lesson-editor' },
+      { label: 'Keine Freistunden', testId: 'class-no-gaps-editor' },
+      { label: 'Fach benoetigt Raumtyp', testId: 'room-requires-type-editor' },
+      { label: 'Raum nicht verfuegbar', testId: 'room-unavailable-editor' },
+    ]
+    for (const c of cases) {
+      await page.getByRole('button', { name: c.label, exact: true }).click()
+      await expect(page.getByTestId(c.testId)).toBeVisible()
+    }
+  })
+
+  test('both Max. Stunden / Tag entries mount the right editor', async ({ page }) => {
+    // The label appears twice (Lehrer + Klasse). .first() targets the
+    // teacher entry (earlier in the DOM), .nth(1) the class entry.
+    const buttons = page.getByRole('button', { name: 'Max. Stunden / Tag', exact: true })
+    await buttons.first().click()
+    await expect(page.getByTestId('teacher-max-hours-day-editor')).toBeVisible()
+    await buttons.nth(1).click()
+    await expect(page.getByTestId('class-max-hours-day-editor')).toBeVisible()
   })
 })