feat(21-22): agente AI generazione preventivo + pagina pubblica deck

- Migration 0010: tabella proposals (id, slug, lead_id, client_id,
  offer_macro_id, content jsonb, state, selected_tier, accepted_at)
  applicata a prod via SSH tunnel
- @anthropic-ai/sdk@0.105.0 installato; ANTHROPIC_API_KEY in .env.local
- src/lib/proposal/: schema Zod ProposalContent, agente Claude Opus 4.8,
  assemble (AI + offerta DB + config consulente), queries, profile.ts
- Admin: /admin/preventivi lista + /genera (pre-fill ?lead_id=X) + /[id] review
- Sidebar: voce Preventivi + CTA globale lime "Genera preventivo"
- LeadDetail: pulsante "Genera preventivo" → /admin/preventivi/genera?lead_id=X
- Pagina pubblica /preventivo/[slug]: deck 20+ slide light-mode iamcavalli,
  navigazione frecce + dot + keyboard, accept/reject con guard immutabilità
- STATE.md aggiornato (80%), 21-PLAN.md scritto nel formato GSD

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/admin/leads/LeadDetail.tsx

@@ -10,6 +10,7 @@ import { OptionMultiSelect } from "@/components/ui/option-multi-select";
 import { addLeadTag, removeLeadTag, renameLeadTag, deleteTranscript } from "@/app/admin/leads/actions";
 import { formatDistanceToNow, format } from "date-fns";
 import { it } from "date-fns/locale";
+import Link from "next/link";
 import { LogActivityModal } from "./LogActivityModal";
 import { SendQuoteModal } from "./SendQuoteModal";
 import { EditLeadModal } from "./LeadForm";
@@ -99,6 +100,12 @@ export function LeadDetail({
           <LogActivityModal leadId={lead.id} />
           <TranscriptModal leadId={lead.id} />
           <SendQuoteModal leadId={lead.id} />
+          <Link
+            href={`/admin/preventivi/genera?lead_id=${lead.id}`}
+            className="inline-flex items-center gap-1.5 px-3 py-2 bg-[#DEF168] text-[#1A463C] rounded-md text-sm font-semibold hover:bg-[#d4e85e] transition-colors"
+          >
+            Genera preventivo
+          </Link>
           <EditLeadModal lead={lead} />
         </div>
       </div>