🔧 chore[security]: upgrade next (#31)

## Description of the change
Upgrade Next.js from 15.5.10 to 15.5.18 to pick up the May 2026 security
release. Also align eslint-config-next with the patched Next.js version.

**Ticket:**

## Test plan
Lint and production build both pass locally.

## Loom or screenshots

## Considerations
This follows Vercel’s May 7, 2026 advisory for Next.js 15.x versions
<=15.5.17. Local validation still shows the pre-existing Next.js
workspace-root warning caused by /Users/raj/package-lock.json being
detected above this worktree.

Author: iamrajjoshi

package.json

@@ -30,7 +30,7 @@
     "@typescript-eslint/eslint-plugin": "^8.6.0",
     "@typescript-eslint/parser": "^8.6.0",
     "framer-motion": "^11.5.4",
-    "next": "15.5.10",
+    "next": "15.5.18",
     "prettier": "^3.3.3",
     "react": "^18",
     "react-dom": "^18",
@@ -45,7 +45,7 @@
     "@types/uuid": "^10.0.0",
     "autoprefixer": "^10.4.23",
     "eslint": "^8.41.0",
-    "eslint-config-next": "14.2.11",
+    "eslint-config-next": "15.5.18",
     "eslint-config-prettier": "^9.1.0",
     "eslint-plugin-prettier": "^5.2.1",
     "husky": "^8.0.0",