feat: collections visibility enum (matches recipes) + QR on collection PDF (v0.54.0)

Replaces collections.isPublic (boolean) with collections.visibility
(private/unlisted/public/followers — same enum recipes use). Two-step
migration (0050 adds+backfills, 0051 drops isPublic) since drizzle-kit's
add+drop-in-one-diff rename heuristic needs an interactive prompt we
can't satisfy here.

New collectionVisibleToViewer(viewerId) in lib/visibility.ts mirrors the
existing recipe helper (author always sees own; public/unlisted visible
to anyone; followers-only via the same user_follows EXISTS pattern) —
used by the collection detail page, its print view, fork, and favorite,
replacing their old `or(isPublic, own)` checks.

Create/edit collection dialogs get the same 4-option visibility select
as the recipe form instead of a public/private checkbox.

Collection PDF export now generates a QR code (qrcode, same as the
recipe PDF) linking to /collections/{id}, shown only when visibility is
public/unlisted — same "would an anonymous scanner actually resolve
this" rule as the recipe QR.

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

apps/web/app/(app)/collections/[id]/page.tsx

@@ -4,7 +4,8 @@ import { headers } from "next/headers";
 import Link from "next/link";
 import { Printer, UtensilsCrossed, StickyNote } from "lucide-react";
 import { auth } from "@/lib/auth/server";
-import { db, collections, eq, and, or } from "@epicure/db";
+import { db, collections, eq, and } from "@epicure/db";
+import { collectionVisibleToViewer } from "@/lib/visibility";
 import { RecipeGridCard } from "@/components/recipe/recipe-grid-card";
 import { CollectionRecipesGrid } from "@/components/collections/collection-recipes-grid";
 import { ForkCollectionButton } from "@/components/collections/fork-collection-button";
@@ -32,10 +33,7 @@ export default async function CollectionPage({ params }: Params) {
   const m = getMessages((session.user as { locale?: string }).locale);
 
   const col = await db.query.collections.findFirst({
-    where: and(
-      eq(collections.id, id),
-      or(eq(collections.userId, session.user.id), eq(collections.isPublic, true))
-    ),
+    where: and(eq(collections.id, id), collectionVisibleToViewer(session.user.id)),
     with: {
       recipes: {
         orderBy: (t, { asc }) => asc(t.position),
@@ -63,7 +61,7 @@ export default async function CollectionPage({ params }: Params) {
             </div>
           )}
           <p className="text-sm text-muted-foreground mt-1">
-            {recipeList.length} recipe{recipeList.length !== 1 ? "s" : ""} · {col.isPublic ? "Public" : "Private"}
+            {recipeList.length} recipe{recipeList.length !== 1 ? "s" : ""} · {m.recipe.visibility[col.visibility]}
           </p>
           {isOwner && col.notes && (
             <div className="mt-2 flex items-start gap-2 rounded-lg border bg-muted/30 px-3 py-2 text-sm text-muted-foreground max-w-2xl">
@@ -103,11 +101,11 @@ export default async function CollectionPage({ params }: Params) {
                 initialDescription={col.description}
                 initialNotes={col.notes}
                 initialTags={col.tags}
-                initialIsPublic={col.isPublic}
+                initialVisibility={col.visibility}
               />
             )}
             {isOwner && <DeleteCollectionDialog collectionId={id} />}
-            {!isOwner && col.isPublic && (
+            {!isOwner && (col.visibility === "public" || col.visibility === "unlisted") && (
               <ForkCollectionButton collectionId={id} />
             )}
           </div>

apps/web/app/(app)/collections/explore/page.tsx

@@ -49,7 +49,7 @@ export default async function ExploreCollectionsPage() {
       collectionFavorites,
       and(eq(collectionFavorites.collectionId, collections.id), gte(collectionFavorites.createdAt, sevenDaysAgo))
     )
-    .where(eq(collections.isPublic, true))
+    .where(eq(collections.visibility, "public"))
     .groupBy(collections.id, users.id)
     .orderBy(desc(sql`count(${collectionFavorites.collectionId})`))
     .limit(12);
@@ -63,7 +63,7 @@ export default async function ExploreCollectionsPage() {
     })
     .from(collections)
     .innerJoin(users, eq(collections.userId, users.id))
-    .where(eq(collections.isPublic, true))
+    .where(eq(collections.visibility, "public"))
     .orderBy(desc(collections.createdAt))
     .limit(12);
 

apps/web/app/(app)/collections/page.tsx

@@ -66,7 +66,7 @@ export default async function CollectionsPage({
         name: col.name,
         description: col.description,
         tags: col.tags,
-        isPublic: col.isPublic,
+        visibility: col.visibility,
         recipeCount: countByCollection.get(col.id) ?? 0,
         thumbnails: col.recipes.flatMap((r) => {
           if (!r.recipe) return [];