feat: granular per-category push notification settings

New Settings → Notifications section with a toggle per category (follow,
comment, reply, reaction, rating, mention, leftover-expiring, shared
shopping list) — previously it was all-or-nothing (browser permission only).

userNotificationPrefs (one row per user, defaults all-on so existing users
see no behavior change until they opt out of something). Gated the push
send in the three places that dispatch one: lib/notifications.ts (the 6
in-app notification types), the leftover-expiry cron, and shopping-list-notify
— in-app notification-center entries and email are unaffected, this only
gates the push itself, matching the literal ask.

Verified locally: GET/PUT round-trips correctly, disabling a category
and confirming the settings page renders all 8 toggles.

apps/web/lib/notification-prefs.ts

@@ -0,0 +1,27 @@
+import { db, userNotificationPrefs, eq } from "@epicure/db";
+
+export type NotificationCategory =
+  | "follow" | "comment" | "reply" | "reaction" | "rating" | "mention"
+  | "leftoverExpiring" | "shoppingList";
+
+export type NotificationPrefs = Record<NotificationCategory, boolean>;
+
+const DEFAULT_PREFS: NotificationPrefs = {
+  follow: true, comment: true, reply: true, reaction: true, rating: true, mention: true,
+  leftoverExpiring: true, shoppingList: true,
+};
+
+export async function getNotificationPrefs(userId: string): Promise<NotificationPrefs> {
+  const row = await db.query.userNotificationPrefs.findFirst({ where: eq(userNotificationPrefs.userId, userId) });
+  if (!row) return { ...DEFAULT_PREFS };
+  return {
+    follow: row.follow, comment: row.comment, reply: row.reply, reaction: row.reaction,
+    rating: row.rating, mention: row.mention, leftoverExpiring: row.leftoverExpiring, shoppingList: row.shoppingList,
+  };
+}
+
+/** No row yet means every category defaults to on — same default the DB columns encode. */
+export async function isNotificationCategoryEnabled(userId: string, category: NotificationCategory): Promise<boolean> {
+  const prefs = await getNotificationPrefs(userId);
+  return prefs[category];
+}

apps/web/lib/notifications.ts

@@ -3,6 +3,7 @@ import { randomUUID } from "crypto";
 import { sendPushNotification } from "./push";
 import { sendEmail, notificationEmailHtml } from "./email";
 import { getMessages, formatMessage } from "./i18n/server";
+import { isNotificationCategoryEnabled } from "./notification-prefs";
 
 type NotificationType = "follow" | "comment" | "reply" | "reaction" | "rating" | "mention";
 
@@ -75,9 +76,11 @@ async function dispatchAlerts(opts: CreateNotificationOpts): Promise<void> {
     ? (actor.username ? `/u/${actor.username}` : "/")
     : opts.recipeId ? `/recipes/${opts.recipeId}` : "/";
 
-  void sendPushNotification(opts.userId, { title, body, url }).catch((err) => {
-    console.error("[notifications] push failed", err);
-  });
+  if (await isNotificationCategoryEnabled(opts.userId, opts.type)) {
+    void sendPushNotification(opts.userId, { title, body, url }).catch((err) => {
+      console.error("[notifications] push failed", err);
+    });
+  }
 
   if (recipient.email) {
     const baseUrl = process.env["BETTER_AUTH_URL"] ?? "http://localhost:3000";

apps/web/lib/shopping-list-notify.ts

@@ -1,6 +1,7 @@
 import { db, shoppingLists, shoppingListMembers, eq } from "@epicure/db";
 import { sendPushNotification } from "@/lib/push";
 import { getMessages, formatMessage } from "@/lib/i18n/server";
+import { isNotificationCategoryEnabled } from "@/lib/notification-prefs";
 
 // formatMessage() is a plain {key} interpolator, not ICU-plural-aware, so
 // pluralization has to be resolved to a plain string before it's passed in.
@@ -53,6 +54,8 @@ export async function notifyShoppingListMembers(
 
   await Promise.all(
     recipients.map(async (recipient) => {
+      if (!(await isNotificationCategoryEnabled(recipient.id, "shoppingList"))) return;
+
       const messages = getMessages(recipient.locale);
       const title = messages.notifications.pushTitle.shoppingListUpdate;
       const body =