feat: add changelog and versioning, surface it in admin

Bumps version to 0.2.0 (root + apps/web package.json) and adds
CHANGELOG.md as the canonical human-readable history, mirrored by
apps/web/lib/changelog.ts as the in-app data source (single
ChangelogList component renders both).

- /changelog: user-facing page, linked from the account dropdown.
- /admin/changelog: same list, plus a "Version" card on the admin
  overview dashboard linking to it.

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

apps/web/lib/changelog.ts

@@ -0,0 +1,37 @@
+// Mirrors CHANGELOG.md at the repo root — update both together.
+export const APP_VERSION = "0.2.0";
+
+export type ChangelogEntry = {
+  version: string;
+  date: string;
+  added?: string[];
+  fixed?: string[];
+  notes?: string;
+};
+
+export const CHANGELOG: ChangelogEntry[] = [
+  {
+    version: "0.2.0",
+    date: "2026-07-12",
+    added: [
+      "Batch cooking: generate a single \"mega recipe\" covering several meals at once — merged shopping list, steps tagged per dish, and per-dish storage/reheat guidance.",
+      "Leftover expiry reminders: mark a batch-cook dish as cooked, track its fridge life, and get a reminder before it goes bad.",
+      "\"Cooked it\" photo reviews: attach a photo and written review when rating a recipe.",
+      "Pantry-expiry recipe suggestions on the Pantry page.",
+      "Trending collections: star public collections, browse trending/recent under Collections → Discover.",
+      "Add to collection directly from the recipe list.",
+      "List and compact view modes for the recipe list.",
+    ],
+    fixed: [
+      "Recipe version-comparison diff was unreadable and partially untranslated.",
+      "Print/export pages now always render light, regardless of app theme.",
+      "Presigned photo-upload URLs were signed against an internal-only address in production.",
+      "Recipe list/form UI issues: filter menu closing on every click, tag filter not accepting keystrokes, inconsistent badge styling, missing tooltips, floating save button on long forms.",
+    ],
+  },
+  {
+    version: "0.1.0",
+    date: "earlier",
+    notes: "Initial feature set: recipes, meal planning, shopping lists, pantry tracking, collections, social features, nutrition tracking, admin dashboard, account/billing basics.",
+  },
+];