QA fixes: real listing creation, profile save, favorites, missing pages

- SellItemPage: real file upload + API listing creation + activate
- CreateProfilePage: save profile via PUT /users/profile
- ProductDetailPage: wire edit/delete/message buttons, show edit for owner
- ListingCard: persist favorites via API, show real images
- Footer: connect newsletter subscribe to API
- Router: add /dashboard/listings and /dashboard/saved routes
- Backend: add GET /listings/favorites endpoint
- New pages: MyListingsPage, SavedItemsPage
- Fix unused imports causing build failures

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/prisma/schema.prisma

@@ -39,6 +39,8 @@ enum OfferStatus {
   ACCEPTED
   DECLINED
   COUNTERED
+  CANCELLED
+  EXPIRED
 }
 
 enum NotificationType {
@@ -76,6 +78,14 @@ model User {
   showRating    Boolean   @default(true)
   twoFactorEnabled Boolean @default(false)
   isActive      Boolean   @default(true)
+  notifNewOffer Boolean   @default(true)
+  notifMessages Boolean   @default(true)
+  notifItemSold Boolean   @default(true)
+  notifFavorites Boolean  @default(true)
+  notifEmail    Boolean   @default(true)
+  marketingEmail Boolean  @default(false)
+  resetToken    String?   @unique
+  resetTokenExpiry DateTime?
   createdAt     DateTime  @default(now())
   updatedAt     DateTime  @updatedAt
 
@@ -155,6 +165,7 @@ model Offer {
   message       String?
   status        OfferStatus @default(PENDING)
   counterAmount Float?
+  expiresAt     DateTime?
   buyerId       String
   sellerId      String
   listingId     String