v1.6.8: remove offer exchange rate, add invoice item description, offer filters, table animations

- Remove exchange_rate and exchange_rate_date from quotations (schema, service, PDF, form)
- Add item_description field to invoice_items (schema, migration, service, form, PDF)
- Add offer status/customer/order filters with tab-based UI
- Clean up offer statuses to active/ordered/invalidated
- Allow invalidate action for non-ordered offers (not just expired)
- Add fade animations on offers and invoices table data changes

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/routes/admin/offers-pdf.ts

@@ -199,7 +199,6 @@ const TRANSLATIONS: Record<string, Record<string, string>> = {
   subtotal: { EN: "Subtotal", CZ: "Mezisou\u010Det" },
   vat: { EN: "VAT", CZ: "DPH" },
   total_to_pay: { EN: "Total to pay", CZ: "Celkem k \u00FAhrad\u011B" },
-  exchange_rate: { EN: "Exchange rate", CZ: "Sm\u011Bnn\u00FD kurz" },
   ico: { EN: "ID", CZ: "I\u010CO" },
   dic: { EN: "VAT ID", CZ: "DI\u010C" },
   page: { EN: "Page", CZ: "Strana" },
@@ -262,8 +261,6 @@ export default async function offersPdfRoutes(
         const vatRate = Number(quotation.vat_rate) || 21;
         const vatAmount = applyVat ? subtotal * (vatRate / 100) : 0;
         const totalToPay = subtotal + vatAmount;
-        const exchangeRate = Number(quotation.exchange_rate) || 0;
-
         let hasScopeContent = false;
         for (const s of quotation.scope_sections) {
           if ((s.content || "").trim() || (s.title || "").trim()) {
@@ -331,10 +328,6 @@ export default async function offersPdfRoutes(
       <span class="label">${escapeHtml(t("total_to_pay"))}</span>
       <span class="value">${formatCurrency(totalToPay, currency)}</span>
     </div>`;
-        if (exchangeRate > 0) {
-          totalsHtml += `<div class="exchange-rate">${escapeHtml(t("exchange_rate"))}: ${formatNum(exchangeRate, 4)}</div>`;
-        }
-
         const quotationNumber = escapeHtml(quotation.quotation_number);
 
         let scopeHtml = "";