fix: correct JSDoc comment (Next.js Request, not Fastify)

The PR #92 incorrectly changed the JSDoc to say "Fastify request object".
This is a Next.js API route that uses the standard Web Request API.

Co-authored-by: jaseel0 <225665919+jaseel0@users.noreply.github.com>
Agent-Logs-Url: https://github.com/BeyteFlow/ReadmeGenAI/sessions/486edd1a-2457-4589-b5e2-b61f6dfde55f

Author: Copilot

src/app/api/generate/route.ts

@@ -9,7 +9,7 @@ export const dynamic = "force-dynamic";
  * AI README Generation Endpoint
  * Optimized for data accuracy, clean prompt interpolation, and multi-language support.
  *
- * @param {Request} req - The incoming Fastify request object containing the repo URL and optional language.
+ * @param {Request} req - The incoming request object containing the repo URL and optional language.
  * @returns {Promise<NextResponse>} A JSON response containing the generated Markdown or an error message.
  */
 export async function POST(req: Request) {