Add Bloch sphere tab with qubit selection dropdown

package.json

@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "three": "^0.179.1"
+  }
+}

qubitverse/visualizer/src/App.jsx

@@ -1,16 +1,23 @@
-import React, { useState, useRef } from 'react';
+import React, { useState } from "react";
 import QuantumCircuit from "./components/QuantumCircuit";
 import "./App.css";
 import Navbar from "./components/Navbar";
 import NQubitInput from "./components/NQubitInput";
+import BlochSphere from "./components/BlochSphere";
 
 function App() {
   const [nQubits, setNQubits] = useState(null);
+  const [showBloch, setShowBloch] = useState(false);
 
   return (
     <>
-      <Navbar />
-      {nQubits === null ? (
+      <Navbar
+        onBlochToggle={() => setShowBloch(!showBloch)}
+        isBlochActive={showBloch}
+      />
+      {showBloch ? (
+        <BlochSphere key="bloch-sphere" />
+      ) : nQubits === null ? (
         <NQubitInput numQubits={nQubits} setQubits={setNQubits} />
       ) : (
         <QuantumCircuit numQubits={nQubits} setNumQubits={setNQubits} />
@@ -19,4 +26,4 @@ function App() {
   );
 }
 
-export default App;
+export default App;