test(mobile): seed the store the location hint is actually read from

useLocationBias reads useTripStore; the sheet's harness only ever built a
planner prop. So the hook saw an empty store, sent no hint, and the one case
that asserts a box went red while its three siblings passed vacuously - they
expect undefined, which an empty store produces no matter what they seed.

capturedBias now seeds places, assignments and selectedDayId the way the
running app has them, which puts all four cases back to work. The 500km case
is retargeted from Tokyo/Sapporo to Tokyo/Nagoya: 264km across, biased under
the old diagonal rule and dropped under the 60km radius one, so it guards the
rule that actually shipped. A new 029b pins the day-first precedence - a trip
too wide to bias still hints at the day being planned.

client/tests/unit/mobile/trip/MPlaceEditSheet.test.tsx

@@ -5,7 +5,9 @@ import type { TripPlanner } from '../../../../src/mobile/screens/trip/MTripShell
 import type { Assignment, Category, Place } from '../../../../src/types'
 import { buildPlanner } from '../../../helpers/mobileTrip'
 import { useAddonStore } from '../../../../src/store/addonStore'
+import { useTripStore } from '../../../../src/store/tripStore'
 import { server } from '../../../helpers/msw/server'
+import { resetAllStores, seedStore } from '../../../helpers/store'
 import { fireEvent, render, screen, waitFor } from '../../../helpers/render'
 
 // FE-MOB-PLEDIT-001 to FE-MOB-PLEDIT-024, plus FE-MOB-PLEDIT-033 to -035
@@ -38,6 +40,7 @@ const submit = () => screen.getByRole('button', { name: /^(common\.add|common\.s
 
 describe('MPlaceEditSheet', () => {
   beforeEach(() => {
+    resetAllStores()
     server.use(
       http.post('/api/maps/search', () => HttpResponse.json({
         source: 'osm',
@@ -354,32 +357,57 @@ describe('MPlaceEditSheet', () => {
     expect(screen.queryByText('ticket.png')).not.toBeInTheDocument()
   })
 
-  /** Types into the search row and returns the bias the autocomplete request carried. */
-  async function capturedBias(places: Place[]) {
+  /**
+   * Types into the search row and returns the bias the autocomplete request
+   * carried. The hint comes from useLocationBias, which reads the trip store,
+   * not the planner prop, so both are seeded the way the running app has them.
+   */
+  async function capturedBias(places: Place[], day?: { id: number; placeIds: number[] }) {
     const bodies: Record<string, unknown>[] = []
     server.use(http.post('/api/maps/autocomplete', async ({ request }) => {
       bodies.push(await request.json() as Record<string, unknown>)
       return HttpResponse.json({ source: 'osm', suggestions: [] })
     }))
+    seedStore(useTripStore, {
+      places,
+      assignments: day ? { [String(day.id)]: day.placeIds.map(id => ({ place_id: id })) } : {},
+      selectedDayId: day?.id ?? null,
+    })
     setup({ places })
     fireEvent.change(screen.getByPlaceholderText('places.mapsSearchPlaceholder'), { target: { value: 'ueno' } })
     await waitFor(() => expect(bodies).toHaveLength(1))
     return bodies[0].locationBias
   }
 
-  it('FE-MOB-PLEDIT-029: biases the maps search on the trip bounding box', async () => {
+  it('FE-MOB-PLEDIT-029: biases the maps search on the trip box while the trip fits one region', async () => {
     const places = [
       { id: 1, name: 'A', lat: 35.6, lng: 139.7 },
       { id: 2, name: 'B', lat: 35.8, lng: 139.9 },
       { id: 3, name: 'C', lat: null, lng: null },
     ] as unknown as Place[]
+    // 25km across and no day open, so the trip is the best hint there is.
     expect(await capturedBias(places)).toEqual({ low: { lat: 35.6, lng: 139.7 }, high: { lat: 35.8, lng: 139.9 } })
   })
 
-  it('FE-MOB-PLEDIT-030: drops the bias for a trip that spans more than 500 km', async () => {
+  it('FE-MOB-PLEDIT-029b: narrows the bias to the open day when the trip is too wide for one', async () => {
+    const places = [
+      { id: 1, name: 'Ueno', lat: 35.71, lng: 139.77 },
+      { id: 2, name: 'Asakusa', lat: 35.71, lng: 139.8 },
+      { id: 3, name: 'Nagoya', lat: 35.18, lng: 136.91 },
+    ] as unknown as Place[]
+    // The trip reaches Nagoya and is dropped, but the day being planned still
+    // gets a hint. That is what preferring the day buys.
+    expect(await capturedBias(places, { id: 7, placeIds: [1, 2] })).toEqual({
+      low: { lat: 35.71, lng: 139.77 }, high: { lat: 35.71, lng: 139.8 },
+    })
+  })
+
+  it('FE-MOB-PLEDIT-030: drops the bias for a trip that outgrows one region', async () => {
+    // Tokyo to Nagoya, 264km across: inside the old 500km diagonal rule, outside
+    // the 60km radius one. A box that wide has its centre in open country.
     const places = [
       { id: 1, name: 'Tokyo', lat: 35.68, lng: 139.76 },
-      { id: 2, name: 'Sapporo', lat: 43.06, lng: 141.35 },
+      { id: 2, name: 'Nagoya', lat: 35.18, lng: 136.91 },
     ] as unknown as Place[]
     expect(await capturedBias(places)).toBeUndefined()
   })