chore(18-01): remove quote builder route, exclusive components, and SendQuoteModal entry point (CLEAN-02)

- Delete src/app/admin/quotes/new/page.tsx and actions.ts re-export
- Delete QuoteBuilderForm, OfferSelector, PriceOverrideInput, QuotePreview components
- Rewrite SendQuoteModal: remove "Crea Nuovo" tab and window.location navigation to quotes/new
- Remove stale JSDoc comment referencing /admin/quotes/new from admin-queries.ts

src/app/admin/quotes/new/actions.ts

@@ -1,3 +0,0 @@
-"use server";
-
-export { createQuote } from "@/lib/quote-actions";

src/app/admin/quotes/new/page.tsx

@@ -1,28 +0,0 @@
-import { Card } from "@/components/ui/card";
-import { QuoteBuilderForm } from "@/components/admin/quotes/QuoteBuilderForm";
-import { getAllClientsWithPayments } from "@/lib/admin-queries";
-import { getAllOfferMacrosWithMicros } from "@/lib/admin-queries";
-
-export const revalidate = 0;
-
-export default async function QuoteBuilderPage() {
-  const [clientsData, offersData] = await Promise.all([
-    getAllClientsWithPayments(),
-    getAllOfferMacrosWithMicros(),
-  ]);
-
-  return (
-    <div className="space-y-6">
-      <div>
-        <h1 className="text-3xl font-bold text-gray-900">Crea Preventivo</h1>
-        <p className="text-gray-600 mt-1">
-          Componi un preventivo per il cliente selezionando l'offerta e il prezzo
-        </p>
-      </div>
-
-      <Card className="p-6">
-        <QuoteBuilderForm clients={clientsData} offerMacros={offersData} />
-      </Card>
-    </div>
-  );
-}