fix: refresh invalid last pickup timestamps

Force an immediate member refresh for legacy epoch timestamps so they are
replaced by the correct no-pickup status without waiting for the weekly check.

.commitmessage

@@ -1,4 +1,4 @@
-fix: show membership date for stores without pickups
+fix: refresh invalid last pickup timestamps
 
-Treat Foodsharing's zero lastFetch value as no pickup, store memberSince, and
-show compact, visible mobile status information without hover tooltips.
+Force an immediate member refresh for legacy epoch timestamps so they are
+replaced by the correct no-pickup status without waiting for the weekly check.

services/lastPickupInfo.js

@@ -17,6 +17,10 @@ function getStaleLastPickupStoreIds(config = [], now = Date.now()) {
       if (!entry?.id || entry.hidden) {
         return false;
       }
+      const lastPickupAt = parseTimestamp(entry.lastPickupAt);
+      if (entry.lastPickupAt && (!lastPickupAt || lastPickupAt <= 0)) {
+        return true;
+      }
       const checkedAt = parseTimestamp(entry.lastPickupCheckedAt);
       return !checkedAt || now - checkedAt > LAST_PICKUP_INFO_MAX_AGE_MS;
     })

src/utils/lastPickupInfo.test.js

@@ -12,10 +12,11 @@ describe('last pickup info', () => {
       { id: 'missing' },
       { id: 'stale', lastPickupCheckedAt: '2026-07-29T11:59:59.000Z' },
       { id: 'fresh', lastPickupCheckedAt: '2026-07-30T12:00:01.000Z' },
+      { id: 'epoch', lastPickupAt: '1970-01-01T00:00:00.000Z', lastPickupCheckedAt: '2026-08-05T12:00:00.000Z' },
       { id: 'hidden', hidden: true }
     ];
 
-    expect(getStaleLastPickupStoreIds(config, now)).toEqual(['missing', 'stale']);
+    expect(getStaleLastPickupStoreIds(config, now)).toEqual(['missing', 'stale', 'epoch']);
   });
 
   it('records a successful check independently from the pickup date', () => {