chore(build): refactor codebase for production

src/components/Calculator.tsx

@@ -1,4 +1,4 @@
-import { useEffect, useRef, useState, useCallback } from "react";
+import { useEffect, useRef, useState } from "react";
 import { createPortal } from "react-dom";
 import { X, Calculator, Maximize2, Minimize2 } from "lucide-react";