fix: batch-cook dishes never deducted pantry when marked cooked

Ingredients aren't attributable to individual batch dishes (they're one
merged/shared list for the whole prep session, unlike steps which have
`appliesTo`) — the cooked route's pantry-deduction block was unconditionally
skipped whenever batchDishId was set, so pantry was never touched for any
batch-cook recipe.

Deducts once, on the first dish marked cooked for that recipe+user (checked
via prior cookingHistory rows) — matches the fridge/freezer-day design
intent of "cook the batch once, eat dishes over several days" rather than
deducting (or trying to deduct) per individual dish.

Verified locally: first dish cooked deducted the full recipe's ingredients
from pantry; second dish cooked did not double-deduct.

apps/web/app/api/v1/recipes/[id]/cooked/route.ts

@@ -27,11 +27,21 @@ export async function POST(req: NextRequest, { params }: Params) {
   const parsed = Schema.safeParse(body);
   const data = parsed.success ? parsed.data : { deductFromPantry: true };
 
+  // Ingredients aren't attributable to individual batch dishes — they're one
+  // merged/shared list for the whole prep session (unlike steps, which have
+  // `appliesTo`). So pantry deduction for a batch-cook recipe happens once,
+  // on the first dish marked cooked, rather than per-dish.
+  let isFirstBatchCook = false;
   if (data.batchDishId) {
     const dish = await db.query.recipeBatchDishes.findFirst({
       where: and(eq(recipeBatchDishes.id, data.batchDishId), eq(recipeBatchDishes.recipeId, id)),
     });
     if (!dish) return NextResponse.json({ error: "Dish not found" }, { status: 404 });
+
+    const priorCook = await db.query.cookingHistory.findFirst({
+      where: and(eq(cookingHistory.recipeId, id), eq(cookingHistory.userId, userId)),
+    });
+    isFirstBatchCook = !priorCook;
   }
 
   await db.insert(cookingHistory).values({
@@ -44,11 +54,14 @@ export async function POST(req: NextRequest, { params }: Params) {
     cookedAt: new Date(),
   });
 
-  if (data.deductFromPantry && !data.batchDishId) {
+  if (data.deductFromPantry && (!data.batchDishId || isFirstBatchCook)) {
     const ings = await db.query.recipeIngredients.findMany({
       where: eq(recipeIngredients.recipeId, id),
     });
-    const scale = data.servings ? data.servings / recipe.baseServings : 1;
+    // A batch session's merged ingredient list is deducted once as a whole,
+    // regardless of which single dish triggered the first cook — never
+    // scaled by that one dish's serving count.
+    const scale = data.batchDishId ? 1 : (data.servings ? data.servings / recipe.baseServings : 1);
     const userPantry = await db.query.pantryItems.findMany({
       where: eq(pantryItems.userId, userId),
     });