feat: implement remaining TODO.md feature ideas + fix mobile headers

Implements the six previously-unscoped feature ideas plus a mobile
layout fix reported via screenshot:

- Mobile: Recipes/Collections/Pantry/Meal Plan/Shopping Lists headers
  now stack and wrap instead of clipping buttons on narrow viewports.
- Recipe diff/compare view: word/list diff against any past version,
  next to Restore in version history.
- Shared meal plans & shopping lists: new shoppingListMembers/
  mealPlanMembers tables (viewer/editor roles, mirrors
  collectionMembers), share dialogs, membership-checked routes.
- PDF cookbook export: /print/collection/[id] renders a whole
  collection with page breaks, using the existing print-CSS pattern
  instead of adding a PDF rendering dependency.
- Grocery delivery handoff: shopping lists can copy-as-text (works
  today) or send to Instacart once INSTACART_API_KEY is configured
  (stub adapter — real API needs a partner agreement).
- Personalized "For You" feed tab: ranks public recipes by tag/
  dietary overlap with the user's favorited/highly-rated history.
- PWA: added manifest.json + icons on top of the existing service
  worker so the app is installable; cook-mode pages were already
  cached for offline use.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/components/recipe/can-cook-content.tsx

@@ -2,7 +2,7 @@
 
 import Link from "next/link";
 import { useTranslations } from "next-intl";
-import { Package } from "lucide-react";
+import { Package, Clock } from "lucide-react";
 import { Badge } from "@/components/ui/badge";
 import { Progress } from "@/components/ui/progress";
 import { buttonVariants } from "@/components/ui/button";
@@ -19,6 +19,7 @@ type ScoredItem = {
   total: number;
   pct: number;
   missing: string[];
+  usesExpiring: string[];
 };
 
 type Props = {
@@ -40,7 +41,15 @@ function RecipeRow({ s }: { s: ScoredItem }) {
         <div className="h-14 w-14 rounded-lg bg-muted shrink-0" />
       )}
       <div className="flex-1 min-w-0 space-y-1">
-        <p className="font-medium truncate">{s.recipe.title}</p>
+        <div className="flex items-center gap-2">
+          <p className="font-medium truncate">{s.recipe.title}</p>
+          {s.usesExpiring.length > 0 && (
+            <Badge variant="outline" className="shrink-0 text-orange-500 border-orange-500 gap-1">
+              <Clock className="h-3 w-3" />
+              {t("useItUp")}
+            </Badge>
+          )}
+        </div>
         <div className="flex items-center gap-2">
           <Progress value={s.pct} className="h-1.5 flex-1 max-w-[120px]" />
           <span className="text-xs text-muted-foreground">