feat: add user selection flow

frontend/src/test/setup.ts

@@ -1,2 +1,27 @@
 import '@testing-library/jest-dom/vitest'
 
+const storedValues = new Map<string, string>()
+
+Object.defineProperty(window, 'localStorage', {
+  configurable: true,
+  value: {
+    get length() {
+      return storedValues.size
+    },
+    clear() {
+      storedValues.clear()
+    },
+    getItem(key: string) {
+      return storedValues.get(key) ?? null
+    },
+    key(index: number) {
+      return [...storedValues.keys()][index] ?? null
+    },
+    removeItem(key: string) {
+      storedValues.delete(key)
+    },
+    setItem(key: string, value: string) {
+      storedValues.set(key, String(value))
+    },
+  } satisfies Storage,
+})