Resolve plural tiers through the i18n context

Importing the plural helper directly from the dashboard trend tile cost
~78 KB gz across the route chunks: the module is tiny, but a new edge
from a widely-instantiated component gets duplicated into every chunk
that contains it rather than hoisted. The provider is already in every
chunk, so expose a plural-aware tCount() there and let components call
that instead. Total client JS goes back under budget.

Also fix the two tests the honest-loading-state change invalidated: the
mental-wellbeing landing tests seeded a never-resolving read and so now
render skeletons rather than instrument cards, and the achievements page
needs a router in scope for its module-gate redirect.

src/components/charts/trend-card.tsx

@@ -10,7 +10,6 @@ import {
   TooltipTrigger,
 } from "@/components/ui/tooltip";
 import { useTranslations, useFormatters } from "@/lib/i18n/context";
-import { pluralKey } from "@/lib/i18n/plural";
 import type { ComparisonBaseline } from "@/lib/dashboard-layout";
 import {
   getTrendSentiment,
@@ -131,7 +130,7 @@ export function TrendCard({
   emptyHint = null,
   valueAdornment = null,
 }: TrendCardProps) {
-  const { t, locale } = useTranslations();
+  const { t, tCount } = useTranslations();
   const fmt = useFormatters();
 
   // v1.4.33 F5 — pick a single signal to drive both the arrow and the
@@ -371,14 +370,10 @@ export function TrendCard({
               }
               if (staleDays <= 60) {
                 const weeks = Math.floor(staleDays / 7);
-                return t(pluralKey("dashboard.staleHintWeeks", weeks, locale), {
-                  count: weeks,
-                });
+                return tCount("dashboard.staleHintWeeks", weeks);
               }
               const months = Math.floor(staleDays / 30);
-              return t(pluralKey("dashboard.staleHintMonths", months, locale), {
-                count: months,
-              });
+              return tCount("dashboard.staleHintMonths", months);
             })()}
           </span>
         )}

src/components/mental-health/__tests__/mental-wellbeing.test.tsx

@@ -3,6 +3,7 @@ import { renderToStaticMarkup } from "react-dom/server";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 
 import { I18nProvider } from "@/lib/i18n/context";
+import { queryKeys } from "@/lib/query-keys";
 import en from "../../../../messages/en.json";
 
 /**
@@ -35,6 +36,15 @@ function withProviders(node: React.ReactNode): string {
   const queryClient = new QueryClient({
     defaultOptions: { queries: { retry: false } },
   });
+  // The landing now distinguishes loading from an empty record: while the
+  // history read is in flight it paints skeletons rather than the instrument
+  // cards' "not taken yet" copy, since that copy is a claim about the user's
+  // record. These tests exercise the LOADED landing, so seed the read as a
+  // settled empty result. The failed and in-flight states are covered in
+  // `failed-read-never-empty.test.tsx`.
+  queryClient.setQueryData(queryKeys.mentalHealthAssessments(), {
+    assessments: [],
+  });
   return renderToStaticMarkup(
     <QueryClientProvider client={queryClient}>
       <I18nProvider initialLocale="en">{node}</I18nProvider>