VSCode doesn't show import suggestion from outside next js app directory

Question

I'm developing a next js project on VSCode. import suggestion for functions and components within app directory works without problem but if I want to import a function from a folder outside app directory (in my case, lib folder) it doesn't show suggestions.

tsconfig:

  "compilerOptions": {
    "target": "es5",
    "lib": [
      "dom",
      "dom.iterable",
      "esnext"
    ],
    "strict": true,
    "noEmit": true,
    "esModuleInterop": true,
    "module": "esnext",
    "moduleResolution": "bundler",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "jsx": "preserve",
    "incremental": true,
    "checkJs": true,
    "plugins": [
      {
        "name": "next"
      }
    ],
    "paths": {
      "@/*": [
        "./*"
      ]
    },
    "skipLibCheck": true,
    "allowJs": true
  },
  "include": [
    "next-env.d.ts",
    "**/*.ts",
    "**/*.tsx",
    ".next/types/**/*.ts"
  ],
  "exclude": [
    "node_modules"
  ]
}

.eslintrc:

{
  "extends": "next/core-web-vitals"
}

next.config:

/** @type {import('next').NextConfig} */
const nextConfig = {}

module.exports = nextConfig

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