feat(showcase): add PouchDB sample component and storage page

- Implemented PouchSample component for managing POS configurations and item inventories using PouchDB.
- Created StoragePage to encapsulate the PouchSample component.
- Added UI components page with various UI elements including buttons, forms, and data grids.
- Defined Electron type declarations for printing and auto-update functionalities.
- Extended event registry with custom application events for printing and stock updates.
- Configured Vite for the showcase application with React and Tailwind CSS support.
- Updated package.json and pnpm-lock.yaml to include necessary dependencies for the showcase app.

apps/showcase/package.json

@@ -0,0 +1,48 @@
+{
+  "name": "showcase",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite --clearScreen false",
+    "build": "tsc && vite build",
+    "preview": "vite preview",
+    "lint": "eslint \"src/**/*.ts\"",
+    "test": "vitest run",
+    "test:watch": "vitest --watch",
+    "typecheck": "tsc --noEmit"
+  },
+  "dependencies": {
+    "@hookform/resolvers": "^5.0.1",
+    "@repo/core-api": "workspace:*",
+    "@repo/core-events": "workspace:*",
+    "@repo/core-i18n": "workspace:*",
+    "@repo/core-storage": "workspace:*",
+    "@repo/ui": "workspace:*",
+    "@repo/utils": "workspace:*",
+    "@tailwindcss/vite": "^4.1.18",
+    "dayjs": "^1.11.19",
+    "events": "^3.3.0",
+    "i18next": "^24.2.2",
+    "lucide-react": "^1.22.0",
+    "react": "^19.2.3",
+    "react-dom": "^19.2.3",
+    "react-hook-form": "^7.56.4",
+    "react-i18next": "^15.4.0",
+    "react-router-dom": "^7.11.0",
+    "tailwindcss": "^4.1.18",
+    "zod": "^3.25.36",
+    "zustand": "^5.0.14"
+  },
+  "devDependencies": {
+    "@repo/eslint-config": "workspace:*",
+    "@repo/typescript-config": "workspace:*",
+    "@types/react": "^19.2.7",
+    "@types/react-dom": "^19.2.3",
+    "@vitejs/plugin-react": "^5.1.2",
+    "eslint": "^8.57.1",
+    "typescript": "5.5.4",
+    "vite": "^5.1.4",
+    "vitest": "^4.0.17"
+  }
+}