fix: varied gradient+icon placeholders for recipes without a cover photo (v0.50.2)

Replaces the single flat emoji-on-muted-bg fallback (same 🍽️/🍹 everywhere)
with a deterministic gradient + food/drink icon per recipe id — pulled from
a small curated palette/icon pool via a string hash, so it's stable across
re-renders but visually varied across a grid of photo-less recipes.

New shared lib/recipe-placeholder.ts + components/recipe/recipe-cover-
placeholder.tsx, applied everywhere the old inline emoji fallback lived:
recipe-grid-card.tsx, recipe-card.tsx, recipes-grid.tsx, and the public
profile page's recipe grid.

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

apps/web/lib/changelog.ts

@@ -1,5 +1,5 @@
 // Mirrors CHANGELOG.md at the repo root — update both together.
-export const APP_VERSION = "0.50.1";
+export const APP_VERSION = "0.50.2";
 
 export type ChangelogEntry = {
   version: string;
@@ -11,6 +11,13 @@ export type ChangelogEntry = {
 };
 
 export const CHANGELOG: ChangelogEntry[] = [
+  {
+    version: "0.50.2",
+    date: "2026-07-19 10:15",
+    fixed: [
+      "Recipes without a cover photo now get a varied gradient + food/drink icon instead of the same flat emoji everywhere — deterministic per recipe, so it stays stable across reloads. Applied to the Recipes grid/list, Explore/collections cards, and public profile pages.",
+    ],
+  },
   {
     version: "0.50.1",
     date: "2026-07-19 09:30",