v1.8.0: warehouse module (16 commits), docházka mzda model, leave_type=holiday removal, api.ts race fix

Highlights:
- Warehouse module: receipts, issues, reservations, inventory, reports, dashboard,
  master data (categories, suppliers, locations), FIFO service, integration tests
- Docházka: mzda PDF counting model (Odpracováno / Vč. svátků / Přesčas / Svátek /
  So/Ne / Noc) with Czech weekday names and decimal hours
- AttendanceAdmin/AttendanceHistory KPI cards unified to mzda formula with
  fund bar colored by delta, badges for Práce/Dov/Nem/Sv/Nep
- Remove leave_type=holiday entirely (auto-computed from Czech public holidays)
- Allow multiple work shifts per day (overlap detection only)
- Pre-flight refresh in api.ts eliminates spurious 401s on fresh page loads
- Prisma: company_settings gets 6 nullable columns for warehouse numbering
  (PRI/VYD/INV prefixes, default patterns); migration seeds defaults

src/utils/html-to-pdf.ts

@@ -41,19 +41,32 @@ async function getBrowser(): Promise<Browser> {
 export async function htmlToPdf(html: string): Promise<Buffer> {
   const b = await getBrowser();
   const page = await b.newPage();
+  // Per-request timeouts so one stuck render (e.g. image tag pointing at a
+  // hung host) cannot starve every subsequent PDF request. networkidle0 is
+  // intentionally NOT used — it waits for 500ms of zero network connections
+  // and is the original source of the indefinite-hang bug.
   try {
-    await page.setContent(html, { waitUntil: "networkidle0" });
+    await page.setContent(html, {
+      waitUntil: "domcontentloaded",
+      timeout: 10_000,
+    });
     const pdf = await page.pdf({
       format: "A4",
       printBackground: true,
       margin: { top: "10mm", bottom: "10mm", left: "10mm", right: "10mm" },
+      timeout: 15_000,
     });
     return Buffer.from(pdf);
   } finally {
     try {
       await page.close();
     } catch {
-      await closeBrowser();
+      // If a stuck page won't close, only close the whole browser if it
+      // is actually disconnected — otherwise we just spent 1-2s relaunching
+      // Chromium on every subsequent PDF request.
+      if (!browser?.connected) {
+        await closeBrowser();
+      }
     }
   }
 }