fix(i18n): translate remaining recipe card/detail strings, localize AI responses

Recipe cards, the recipe detail page, and meal planner still rendered raw
"{n} servings"/"{n}m cook"/"{n} srv" text and untranslated difficulty labels
outside the earlier i18n pass. Also wires the user's locale into AI features
that previously always answered in English regardless of app language:
recipe chat, ingredient substitution, recipe ideas, and generate-from-idea.
The recipe-language picker in the AI generate dialog now defaults to the
user's locale instead of always defaulting to English.

apps/web/components/search/search-page-content.tsx

@@ -2,6 +2,7 @@
 
 import { useState, useEffect, useRef, useCallback } from "react";
 import { useRouter, useSearchParams } from "next/navigation";
+import { useTranslations } from "next-intl";
 import Link from "next/link";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
@@ -39,7 +40,11 @@ const DIFFICULTY_COLORS: Record<string, string> = {
 };
 
 function RecipeCard({ recipe }: { recipe: RecipeResult }) {
+  const t = useTranslations("recipe");
   const totalMins = (recipe.prepMins ?? 0) + (recipe.cookMins ?? 0);
+  const difficultyLabel = recipe.difficulty === "easy" || recipe.difficulty === "medium" || recipe.difficulty === "hard"
+    ? t(`difficulty.${recipe.difficulty}`)
+    : recipe.difficulty;
   return (
     <Link
       href={`/recipes/${recipe.id}`}
@@ -54,7 +59,7 @@ function RecipeCard({ recipe }: { recipe: RecipeResult }) {
             variant="secondary"
             className={`shrink-0 capitalize text-xs ${DIFFICULTY_COLORS[recipe.difficulty] ?? ""}`}
           >
-            {recipe.difficulty}
+            {difficultyLabel}
           </Badge>
         )}
       </div>
@@ -65,7 +70,7 @@ function RecipeCard({ recipe }: { recipe: RecipeResult }) {
         {totalMins > 0 && (
           <span className="flex items-center gap-1">
             <Clock className="h-3.5 w-3.5" />
-            {totalMins}m
+            {t("total", { mins: totalMins })}
           </span>
         )}
         {recipe.authorName && (