feat(documents)!: unify offers and issued orders end to end

One coherent pass over the two sibling document models, driven by a 3-lens
1:1 scan (~60 divergences inventoried) + user decisions. Migration adds
issued_orders.locked_by/locked_at and the issued_order_sections table
(mirror of scope_sections; applied to dev + test DBs).

Issued orders gained (offers as reference implementation):
- rich-text SECTIONS with CZ/EN titles, rendered on their own PDF page in
  the PO template's red style (shared DocumentSectionSchema, one-transaction
  create/update incl. items - fixes a torn-write bug)
- edit LOCKING (lock/heartbeat/unlock routes, 423 + holder name, 30s TTL =
  3 missed 10s heartbeats; locked_by enrichment on detail)
- archived-PDF serving: GET /:id/file reads the NAS copy (new
  readIssuedByNumber sweep) with live-render fallback + re-archive; offers'
  /file got the same fallback (kills the 'ulozte nabidku' dead end)
- NAS cleanup on delete, in-tx po_number uniqueness (409), collision-advancing
  number previews (also invoice previews), PUT returns assigned po_number

Offers hardened (issued as reference):
- VALID_TRANSITIONS enforced (no more numberless 'ordered' offers; invalidate
  follows the table; order creation only from active offers) +
  valid_transitions on detail
- explicit 400 instead of silent edits outside draft/active (mirrored on
  issued: explicit 400 replaced silent drops)
- customer existence check + Number(null)->0 clear bug fixed; delete of a
  linked offer -> 409 instead of P2003 500; error-token convention; Zod caps
  DB-aligned (desc 500/unit 20/number 50/project_code 100, isoDateString
  dates, ints for positions); audit old/new values + koncept fallbacks;
  list id tiebreaks; stats include trimmed; NAS delete dedupe

Frontend unification (6 new shared modules):
- components/document/{DocumentItemsEditor,SectionsEditor,LockBanner}
- hooks/{useDocumentLock,useUnsavedChangesGuard,useDocumentPdf(+list variant)}
- OfferDetail 1940->1100 lines, IssuedOrderDetail 1400->980: headline-only
  document number (form field removed), one form layout/readonly convention,
  view-permission opens read-only everywhere (issued's editable-for-viewers
  hole closed), server-driven transition buttons, dirty guard + Enter submit
  on both, useApiMutation everywhere (new opt-in envelope mode), fixed
  infinite spinner on failed detail fetch, draft PDFs hidden (no number yet)
- lists: supplier filter + count line on issued, Mena column dropped + mono
  numbers on offers, shared hardened per-row PDF flow (spinner, double-click
  guard, 401 close, blob cleanup), proper Czech quotes, real CTA empty
  states, query-lib cleanups (["offers","customers"] key, typed list rows,
  shared CurrencyAmount, retry:false on details)
- pdf-shared.ts: one escapeHtml/cleanQuillHtml(strict)/formatNum(NBSP)/
  formatCurrency/formatDate for all four PDF routes; offer PDF keeps its
  monochrome look (fractional qty fix: 1.5 no longer prints as 2); issued
  PDF language now comes from the document column

+49 tests (suite 364 -> 413). Each stage passed an independent review; final
cross-stage integration review verified the FE<->BE contracts.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/__tests__/pdf-no-vat.test.ts

@@ -5,6 +5,8 @@ import prisma from "../config/database";
 import { config } from "../config/env";
 import { renderOrderConfirmationHtml } from "../routes/admin/orders-pdf";
 import offersPdfRoutes from "../routes/admin/offers-pdf";
+import invoicesPdfRoutes from "../routes/admin/invoices-pdf";
+import { createInvoice } from "../services/invoices.service";
 
 // Offers, received orders (their confirmation PDF) and issued orders are NOT
 // tax documents — VAT must never appear on them. These tests pin that contract
@@ -73,6 +75,26 @@ describe("renderOrderConfirmationHtml (order confirmation PDF)", () => {
     );
     // Grand total stays 200,00 — the excluded line doesn't count.
     expect(html).toContain("200,00 CZK");
+  });
+
+  it("uses the shared NBSP-thousands formatter (pdf-shared extraction marker)", () => {
+    const html = renderOrderConfirmationHtml(
+      order,
+      [
+        {
+          description: "Velká položka",
+          quantity: 2,
+          unit: "ks",
+          unit_price: 1000,
+          is_included_in_total: true,
+        },
+      ],
+      null,
+      "cs",
+      "Jan",
+    );
+    // 2 × 1000 = 2 000,00 with the NBSP (U+00A0) thousands separator.
+    expect(html).toContain("2 000,00 CZK");
     expect(html).not.toContain("1 199,00 CZK");
   });
 });
@@ -84,10 +106,12 @@ describe("renderOrderConfirmationHtml (order confirmation PDF)", () => {
 let app: ReturnType<typeof Fastify> | null = null;
 let adminToken = "";
 const createdQuotationIds: number[] = [];
+const createdInvoiceIds: number[] = [];
 
 beforeAll(async () => {
   app = Fastify({ logger: false });
   await app.register(offersPdfRoutes, { prefix: "/api/admin/offers-pdf" });
+  await app.register(invoicesPdfRoutes, { prefix: "/api/admin/invoices-pdf" });
 
   const admin = await prisma.users.findFirst({
     where: { roles: { name: "admin" } },
@@ -103,6 +127,8 @@ beforeAll(async () => {
 afterAll(async () => {
   for (const id of createdQuotationIds)
     await prisma.quotations.deleteMany({ where: { id } });
+  for (const id of createdInvoiceIds)
+    await prisma.invoices.deleteMany({ where: { id } });
   if (app) await app.close();
 });
 
@@ -144,4 +170,78 @@ describe("GET /api/admin/offers-pdf/:id (offer PDF html)", () => {
     expect(html).not.toContain("Mezisoučet");
     expect(html).not.toContain("Celkem k úhradě");
   });
+
+  it("renders a fractional quantity as '1,50', not rounded to '2'", async () => {
+    const quotation = await prisma.quotations.create({
+      data: {
+        quotation_number: `Q-FRACQTY-${Date.now()}`,
+        status: "active",
+        currency: "CZK",
+        language: "cs",
+        quotation_items: {
+          create: [
+            {
+              description: "Půldenní sazba",
+              quantity: 1.5,
+              unit: "ks",
+              unit_price: 1000,
+              is_included_in_total: true,
+              position: 0,
+            },
+          ],
+        },
+      },
+    });
+    createdQuotationIds.push(quotation.id);
+
+    const res = await app!.inject({
+      method: "GET",
+      url: `/api/admin/offers-pdf/${quotation.id}`,
+      headers: { Authorization: `Bearer ${adminToken}` },
+    });
+    expect(res.statusCode).toBe(200);
+    const html = res.body;
+    // The old toFixed(0) ROUNDED 1.5 → "2"; integers still render without
+    // decimals elsewhere (covered by the previous test's qty 2).
+    expect(html).toContain("1,50 / ks");
+    expect(html).not.toContain(">2 / ks<");
+  });
+});
+
+/* -------------------------------------------------------------------------- */
+/* Invoice PDF route — post-pdf-shared-extraction render marker               */
+/* -------------------------------------------------------------------------- */
+
+describe("GET /api/admin/invoices-pdf/:id (invoice PDF html)", () => {
+  it("still renders the invoice HTML after the shared-helper extraction", async () => {
+    // Draft → no number consumed; CZK → no CNB exchange-rate lookup.
+    const invoice = await createInvoice({
+      status: "draft",
+      currency: "CZK",
+      apply_vat: true,
+      vat_rate: 21,
+      items: [
+        {
+          description: "PDF-SHARED-MARKER",
+          quantity: 2,
+          unit_price: 1000,
+          vat_rate: 21,
+        },
+      ],
+    });
+    createdInvoiceIds.push(invoice.id);
+
+    const res = await app!.inject({
+      method: "GET",
+      url: `/api/admin/invoices-pdf/${invoice.id}`,
+      headers: { Authorization: `Bearer ${adminToken}` },
+    });
+    expect(res.statusCode).toBe(200);
+    const html = res.body;
+    expect(html).toContain("FAKTURA - DAŇOVÝ DOKLAD");
+    expect(html).toContain("PDF-SHARED-MARKER");
+    // Shared NBSP formatNum: 2 × 1000 = 2 000,00 base.
+    expect(html).toContain("2 000,00");
+    expect(html).toContain("Celkem k úhradě");
+  });
 });