chore: Update all dependencies to latest versions

Backend updates:
- zod: 3.24.1 → 4.3.6 (major)
- bcryptjs: 2.4.3 → 3.0.3 (major)
- jsonwebtoken: 9.0.2 → 9.0.3 (patch)
- @types/bcryptjs: 2.4.6 → 3.0.0 (major)

Frontend updates:
- next-auth: 5.0.0-beta.25 → 5.0.0-beta.30 (latest v5 beta)
- react: 19.1.0 → 19.2.4 (patch)
- react-dom: 19.1.0 → 19.2.4 (patch)
- recharts: 2.15.4 → 3.7.0 (major)
- tailwind-merge: 2.6.1 → 3.5.0 (major)
- @types/node: 22.12.0 → 25.3.0 (major)
- tailwindcss: 3.4.19 → 4.2.0 (major)

Notes:
- All dependencies updated to absolute latest stable versions
- next-auth kept on v5 beta (upgraded to latest beta.30)
- See DEPENDENCY_UPDATES.md for full details and testing checklist
- Potential breaking changes in zod v4, bcryptjs v3, recharts v3, and tailwindcss v4
- Configuration files may need updates for tailwindcss v4 compatibility

frontend/package.json

@@ -9,10 +9,10 @@
   },
   "dependencies": {
     "next": "16.1.6",
-    "next-auth": "^5.0.0-beta.25",
-    "react": "^19.1.0",
-    "react-dom": "^19.1.0",
-    "recharts": "^2.15.4",
+    "next-auth": "^5.0.0-beta.30",
+    "react": "^19.2.4",
+    "react-dom": "^19.2.4",
+    "recharts": "^3.7.0",
     "lucide-react": "^0.574.0",
     "date-fns": "^4.1.0",
     "@radix-ui/react-dialog": "^1.1.15",
@@ -22,14 +22,14 @@
     "@radix-ui/react-toast": "^1.2.15",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
-    "tailwind-merge": "^2.6.1"
+    "tailwind-merge": "^3.5.0"
   },
   "devDependencies": {
-    "@types/node": "^22.12.0",
+    "@types/node": "^25.3.0",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
     "typescript": "^5.9.3",
-    "tailwindcss": "^3.4.19",
+    "tailwindcss": "^4.2.0",
     "postcss": "^8.5.6",
     "autoprefixer": "^10.4.24"
   }