Added transaction feature, fixed some mistakes

frontend/src/api/families.ts

@@ -0,0 +1,19 @@
+export interface Family {
+  id: number
+  name: string
+  owner_id: number
+  telegram_chat_id: number | null
+  telegram_chat_name: string | null
+  created_at: string
+  updated_at: string
+}
+
+export async function getFamilyById(id: number): Promise<Family> {
+  const response = await fetch(`/api/v1/families/${id}`)
+
+  if (!response.ok) {
+    throw new Error(`Failed to fetch family: ${response.status}`)
+  }
+
+  return response.json() as Promise<Family>
+}