feat: Revamp EPUB import process with batch upload support and enhanced API integration

- Introduced a new batch import client for handling multiple EPUB files simultaneously.
- Updated API routes for previewing and importing EPUB files, improving error handling and response management.
- Enhanced genre management during import, allowing for dynamic creation and association of genres.
- Implemented long-fetch handling to accommodate lengthy processing times for large EPUB files.
- Refined UI components for better user experience in the import workflow.

lib/reader-api-long-fetch.ts

@@ -0,0 +1,19 @@
+import { Agent, fetch as undiciFetch } from "undici"
+
+/** Tránh mặc định undici (headers/body ~300s) cắt kết nối khi API + NAS xử lý lâu. */
+const longRunningAgent = new Agent({
+  connectTimeout: 120_000,
+  headersTimeout: 3_600_000,
+  bodyTimeout: 3_600_000,
+})
+
+export async function readerApiLongFetch(
+  input: string | URL,
+  init?: RequestInit & { duplex?: "half" },
+): Promise<Response> {
+  const res = await undiciFetch(input, {
+    ...init,
+    dispatcher: longRunningAgent,
+  } as Parameters<typeof undiciFetch>[1])
+  return res as unknown as Response
+}