feat: add dedicated model photo separate from avatar

Adds a `photo` field to the users table (and a migration) that serves
as a dedicated profile/card image for models. This is now used in model
cards and on the model single page, while `avatar` is reserved for
comments, article authors, and the user profile page.

- DB: `photo` column on `users` with FK to `files`
- GraphQL: exposed on ModelType, UserType, AdminUserDetailType; photoId arg on adminUpdateUser
- Services: photo field in MODELS_QUERY, MODEL_BY_SLUG_QUERY, ADMIN_GET/UPDATE_USER
- Frontend: model cards and single page use `photo ?? avatar` fallback
- Admin: model photo upload section in user edit page

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

packages/backend/src/db/schema/users.ts

@@ -29,6 +29,7 @@ export const users = pgTable(
     role: roleEnum("role").notNull().default("viewer"),
     avatar: text("avatar").references(() => files.id, { onDelete: "set null" }),
     banner: text("banner").references(() => files.id, { onDelete: "set null" }),
+    photo: text("photo").references(() => files.id, { onDelete: "set null" }),
     is_admin: boolean("is_admin").notNull().default(false),
     email_verified: boolean("email_verified").notNull().default(false),
     email_verify_token: text("email_verify_token"),

packages/backend/src/graphql/resolvers/users.ts

@@ -134,6 +134,7 @@ builder.mutationField("adminUpdateUser", (t) =>
       artistName: t.arg.string(),
       avatarId: t.arg.string(),
       bannerId: t.arg.string(),
+      photoId: t.arg.string(),
     },
     resolve: async (_root, args, ctx) => {
       requireAdmin(ctx);
@@ -149,6 +150,7 @@ builder.mutationField("adminUpdateUser", (t) =>
         updates.artist_name = args.artistName;
       if (args.avatarId !== undefined && args.avatarId !== null) updates.avatar = args.avatarId;
       if (args.bannerId !== undefined && args.bannerId !== null) updates.banner = args.bannerId;
+      if (args.photoId !== undefined && args.photoId !== null) updates.photo = args.photoId;
 
       const updated = await ctx.db
         .update(users)

packages/backend/src/graphql/types/index.ts

@@ -55,6 +55,7 @@ export const UserType = builder.objectRef<User>("User").implement({
     is_admin: t.exposeBoolean("is_admin"),
     avatar: t.exposeString("avatar", { nullable: true }),
     banner: t.exposeString("banner", { nullable: true }),
+    photo: t.exposeString("photo", { nullable: true }),
     email_verified: t.exposeBoolean("email_verified"),
     date_created: t.expose("date_created", { type: "DateTime" }),
   }),
@@ -75,6 +76,7 @@ export const CurrentUserType = builder.objectRef<User>("CurrentUser").implement(
     is_admin: t.exposeBoolean("is_admin"),
     avatar: t.exposeString("avatar", { nullable: true }),
     banner: t.exposeString("banner", { nullable: true }),
+    photo: t.exposeString("photo", { nullable: true }),
     email_verified: t.exposeBoolean("email_verified"),
     date_created: t.expose("date_created", { type: "DateTime" }),
   }),
@@ -133,6 +135,7 @@ export const ModelType = builder.objectRef<Model>("Model").implement({
     description: t.exposeString("description", { nullable: true }),
     avatar: t.exposeString("avatar", { nullable: true }),
     banner: t.exposeString("banner", { nullable: true }),
+    photo: t.exposeString("photo", { nullable: true }),
     tags: t.exposeStringList("tags", { nullable: true }),
     date_created: t.expose("date_created", { type: "DateTime" }),
     photos: t.expose("photos", { type: [ModelPhotoType], nullable: true }),
@@ -416,6 +419,7 @@ export const AdminUserDetailType = builder.objectRef<AdminUserDetail>("AdminUser
     is_admin: t.exposeBoolean("is_admin"),
     avatar: t.exposeString("avatar", { nullable: true }),
     banner: t.exposeString("banner", { nullable: true }),
+    photo: t.exposeString("photo", { nullable: true }),
     email_verified: t.exposeBoolean("email_verified"),
     date_created: t.expose("date_created", { type: "DateTime" }),
     photos: t.expose("photos", { type: [ModelPhotoType] }),

packages/backend/src/migrations/0003_model_photo.sql

@@ -0,0 +1 @@
+ALTER TABLE "users" ADD COLUMN "photo" text REFERENCES "files"("id") ON DELETE set null;