fix(planner): pin the clock in the opening-hours test

FE-PDC-019 asserts that the collapsed row shows one specific line, but the row
shows the current day in the place's timezone — and the fixture gives Saturday
different hours from the working week. So the test passed Monday to Friday and
took the build down every weekend, which reads as a broken feature rather than a
test that forgot to say which day it is standing on.

Pinned to a Wednesday, with the Saturday case kept as its own test rather than
thrown away: it is the one that proves the day lookup happens at all, and it is
the exact case that was failing.

client/src/components/Planner/PlaceDetailsColumn.test.tsx

@@ -307,7 +307,22 @@ describe('PlaceDetailsColumn — hours and rating', () => {
     })
   }
 
+  // The collapsed row shows the CURRENT day in the place's timezone, so a test
+  // that names a specific line has to say which day it is standing on. Without
+  // this the suite passed Monday to Friday and failed every weekend, which reads
+  // as a broken build rather than a test that forgot to pin its clock.
+  // SELECTION is in Cologne, so midday UTC is safely the same date in Berlin.
+  const pinDay = (iso: string) => {
+    vi.useFakeTimers({ shouldAdvanceTime: true })
+    vi.setSystemTime(new Date(iso))
+  }
+
+  afterEach(() => {
+    vi.useRealTimers()
+  })
+
   it('FE-PDC-019: shows only today collapsed, not the whole week', async () => {
+    pinDay('2026-08-12T12:00:00Z') // Wednesday
     withHours()
     renderColumn()
 
@@ -318,6 +333,19 @@ describe('PlaceDetailsColumn — hours and rating', () => {
     expect(screen.queryByText('10:00-14:00')).not.toBeInTheDocument()
   })
 
+  it('FE-PDC-019b: the collapsed row follows the day, it is not just the first line', async () => {
+    // The case that used to take the suite down every Saturday. Worth keeping as
+    // a test rather than only pinning 019: it is the assertion that the day
+    // lookup happens at all.
+    pinDay('2026-08-15T12:00:00Z') // Saturday
+    withHours()
+    renderColumn()
+
+    await screen.findByText('inspector.openingHours')
+    expect(screen.queryAllByText('10:00-14:00')).toHaveLength(1)
+    expect(screen.queryByText('09:00-18:00')).not.toBeInTheDocument()
+  })
+
   it('FE-PDC-020: opens the full week on click', async () => {
     withHours()
     renderColumn()