Fix Home dashboard integration findings (Feature 21)

- F21-01: plan_ready and list_ready links carry their week
  (/plan?week=, /plan/shopping?week=), and the Plan opens on ?week=
  and keeps it on the week shown, so an older update opens its week.
- F21-02: a failed refresh of the Rotation check shows its ErrorBanner
  beside the cached pending card instead of replacing it.
- F21-03: Home carries the household's timezone and is read again at
  its next local midnight.
- F21-04: Home counts pending Side quests through a read-only query
  (suggest.PendingCount), so reading Home never writes batches.

Task: ac3dddf0-a05f-4e43-a5ad-3105fe6bdd95

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/home/RotationCheck.tsx

@@ -44,17 +44,12 @@ function RotationCard({ review, disabled, onDecide }: RotationCardProps) {
 // household answers it — nothing is decided for them. An answer is applied
 // at once: Home confirms it and shows the next pending check, if any, while
 // the answer is saved; the answers are locked until it settles. A failed
-// answer puts its check back with an ErrorBanner.
+// answer puts its check back with an ErrorBanner. A failed read shows an
+// ErrorBanner, beside the checks last read: a card already shown stays
+// until it is answered.
 export function RotationCheck() {
   const reviews = useRotationReviews()
   const decide = useDecideRotationReview()
-  if (reviews.isError) {
-    return (
-      <ErrorBanner onRetry={() => void reviews.refetch()}>
-        Couldn't load the Rotation check. {reviews.error.message}
-      </ErrorBanner>
-    )
-  }
   const deciding = decide.isPending ? decide.variables.review.dinner.id : null
   const next = reviews.data?.find((review) => review.dinner.id !== deciding)
   const answered = decide.isPending || decide.isSuccess ? decide.variables : undefined
@@ -65,6 +60,11 @@ export function RotationCheck() {
           {CONFIRMATION[answered.decision]}
         </p>
       )}
+      {reviews.isError && (
+        <ErrorBanner onRetry={() => void reviews.refetch()}>
+          Couldn't load the Rotation check. {reviews.error.message}
+        </ErrorBanner>
+      )}
       {decide.isError && <ErrorBanner>Couldn't save that answer. {decide.error.message}</ErrorBanner>}
       {next !== undefined && (
         <RotationCard