feat(env): Update environment configuration and enhance email functionality

- Renamed DATABASE_URL to POSTGRES_URL in .env.example for clarity.
- Added SMTP configuration for email sending, including host, port, user, password, and from address.
- Updated package.json to include new dependencies for email handling and UI components.
- Modified middleware to handle public and protected routes more effectively.
- Enhanced API routes for studies to support user roles and permissions.
- Updated database schema to include invitations and user roles related to studies.
- Improved user permissions handling in the permissions module.
- Added new utility functions for managing user roles and study access.

package.json

@@ -3,7 +3,7 @@
   "version": "0.1.0",
   "private": true,
   "scripts": {
-    "dev": "next dev --turbopack",
+    "dev": "next dev",
     "build": "next build",
     "start": "next start",
     "lint": "next lint",
@@ -12,23 +12,29 @@
     "db:seed": "tsx src/db/seed.ts",
     "ngrok:start": "ngrok http --url=endless-pegasus-happily.ngrok-free.app 3000",
     "db:drop": "tsx src/db/drop.ts",
-    "db:reset": "pnpm db:drop && pnpm db:push && pnpm db:seed"
+    "db:reset": "pnpm db:drop && pnpm db:push && pnpm db:seed",
+    "test:email": "tsx src/scripts/test-email.ts"
   },
   "dependencies": {
     "@clerk/nextjs": "^6.4.0",
+    "@radix-ui/react-alert-dialog": "^1.1.2",
     "@radix-ui/react-dialog": "^1.1.2",
     "@radix-ui/react-icons": "^1.3.2",
     "@radix-ui/react-label": "^2.1.0",
     "@radix-ui/react-select": "^2.1.2",
     "@radix-ui/react-slot": "^1.1.0",
+    "@radix-ui/react-tabs": "^1.1.1",
+    "@types/nodemailer": "^6.4.17",
     "@vercel/postgres": "^0.10.0",
     "class-variance-authority": "^0.7.0",
     "clsx": "^2.1.1",
+    "date-fns": "^4.1.0",
     "dotenv": "^16.4.5",
     "drizzle-orm": "^0.36.3",
     "lucide-react": "^0.454.0",
     "next": "15.0.2",
     "ngrok": "5.0.0-beta.2",
+    "nodemailer": "^6.9.16",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
     "svix": "^1.41.0",