feat: cooking history/gallery, unit conversion, nutrition diary, pantry scan, digest cron, nutrition-targeted meal plans

Six M-sized items from HANDOFF.md's new-features backlog:

- Profile tabs: cooking-history stats (total cooked, last-cooked, streak)
  and a "cooked it" photo gallery, both owner-only
- Display-time unit conversion (metric<->imperial) for recipe ingredients,
  respecting each user's unitPref; original value always shown alongside
  the conversion
- Nutrition daily diary: per-day macro totals computed from cooking history
  x recipe nutritionData, compared against user goals
- Pantry scan: real barcode lookup (zxing + Open Food Facts, no API key)
  with an AI-vision fallback for unbarcoded items, always confirm-before-
  insert, both paths tier/rate-limited like other AI features
- Weekly digest email: new followers/comments/ratings + trending recipes,
  sent via a new `cron` Docker stage (alpine+crond+curl) and `digest-cron`
  compose service hitting a bearer-token-protected internal route
- Meal-plan generation can now target a user's nutrition goals as a
  prompt-level nudge (recipes are AI-invented, not DB-sourced, so this
  can't be a hard macro constraint)

Caught a real deploy-breaking issue while adding the cron stage: appending
it after `runner` silently changed the Dockerfile's default build target,
and `web`'s compose config didn't pin one — fixed by pinning `target:
runner` explicitly. Verified with typecheck, lint, and three separate
`docker build --target` runs (runner/cron/migrator) plus `docker compose
config` validation.

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

apps/web/app/print/[id]/page.tsx

@@ -3,7 +3,7 @@ import { headers } from "next/headers";
 import { auth } from "@/lib/auth/server";
 import { db, recipes, eq, and } from "@epicure/db";
 import { PrintTrigger } from "@/components/recipe/print-trigger";
-import { hasQuantity } from "@/lib/fractions";
+import { formatIngredientQuantity } from "@/lib/unit-conversion";
 import { getMessages, formatMessage } from "@/lib/i18n/server";
 
 type Params = { params: Promise<{ id: string }> };
@@ -14,6 +14,7 @@ export default async function RecipePrintPage({ params }: Params) {
   if (!session) return null;
 
   const m = getMessages((session.user as { locale?: string }).locale);
+  const unitPref = (session.user as { unitPref?: string }).unitPref === "imperial" ? "imperial" : "metric";
 
   const recipe = await db.query.recipes.findFirst({
     where: and(eq(recipes.id, id), eq(recipes.authorId, session.user.id)),
@@ -103,7 +104,7 @@ export default async function RecipePrintPage({ params }: Params) {
               {recipe.ingredients.map((ing) => (
                 <li key={ing.id}>
                   <span className="qty">
-                    {[hasQuantity(ing.quantity) ? ing.quantity : null, ing.unit].filter(Boolean).join(" ")}
+                    {formatIngredientQuantity(ing.quantity, ing.unit, unitPref)}
                   </span>
                   {ing.rawName}
                   {ing.note && <span style={{ color: "#888" }}> ({ing.note})</span>}

apps/web/app/print/collection/[id]/page.tsx

@@ -3,7 +3,7 @@ import { headers } from "next/headers";
 import { auth } from "@/lib/auth/server";
 import { db, collections, eq, and, or } from "@epicure/db";
 import { PrintTrigger } from "@/components/recipe/print-trigger";
-import { hasQuantity } from "@/lib/fractions";
+import { formatIngredientQuantity } from "@/lib/unit-conversion";
 import { getMessages, formatMessage } from "@/lib/i18n/server";
 
 type Params = { params: Promise<{ id: string }> };
@@ -14,6 +14,7 @@ export default async function CollectionPrintPage({ params }: Params) {
   if (!session) return null;
 
   const m = getMessages((session.user as { locale?: string }).locale);
+  const unitPref = (session.user as { unitPref?: string }).unitPref === "imperial" ? "imperial" : "metric";
 
   const col = await db.query.collections.findFirst({
     where: and(
@@ -113,7 +114,7 @@ export default async function CollectionPrintPage({ params }: Params) {
                   {recipe.ingredients.map((ing) => (
                     <li key={ing.id}>
                       <span className="qty">
-                        {[hasQuantity(ing.quantity) ? ing.quantity : null, ing.unit].filter(Boolean).join(" ")}
+                        {formatIngredientQuantity(ing.quantity, ing.unit, unitPref)}
                       </span>
                       {ing.rawName}
                       {ing.note && <span style={{ color: "#888" }}> ({ing.note})</span>}