Update Next.js to version 15.4.2 and refactor invoice pages

- Upgrade Next.js and related packages for improved performance and security
- Refactor invoice-related pages to streamline navigation and enhance user experience
- Consolidate invoice editing and viewing functionality into a single page
- Remove deprecated edit page and implement a new view page for invoices
- Update links and routing for consistency across the dashboard

src/app/dashboard/invoices/[id]/_components/unified-invoice-page.tsx

@@ -1,7 +1,7 @@
 "use client";
 
 import { InvoiceView } from "~/components/data/invoice-view";
-import { InvoiceForm } from "~/components/forms/invoice-form";
+import InvoiceForm from "~/components/forms/invoice-form";
 
 interface UnifiedInvoicePageProps {
   invoiceId: string;