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/admin/lib/queries/invoices.ts

@@ -34,7 +34,7 @@ export interface InvoiceStats {
 export interface InvoiceItem {
   id?: number;
   description: string;
-  item_description?: string;
+  item_description: string;
   quantity: number;
   unit: string;
   unit_price: number;

src/admin/lib/queries/offers.ts

@@ -70,6 +70,9 @@ export const offerListOptions = (filters: {
   order?: string;
   page?: number;
   perPage?: number;
+  status?: string;
+  customer_id?: number;
+  has_order?: string;
 }) =>
   queryOptions({
     queryKey: ["offers", "list", filters],
@@ -80,6 +83,10 @@ export const offerListOptions = (filters: {
       if (filters.order) params.set("order", filters.order);
       if (filters.page) params.set("page", String(filters.page));
       if (filters.perPage) params.set("per_page", String(filters.perPage));
+      if (filters.status) params.set("status", filters.status);
+      if (filters.customer_id)
+        params.set("customer_id", String(filters.customer_id));
+      if (filters.has_order) params.set("has_order", filters.has_order);
       const qs = params.toString();
       return paginatedJsonQuery(`/api/admin/offers${qs ? `?${qs}` : ""}`);
     },
@@ -127,7 +134,6 @@ export interface OfferDetailData {
   language: string;
   vat_rate: number;
   apply_vat: boolean;
-  exchange_rate: string;
   scope_title: string;
   scope_description: string;
   items?: OfferItemData[];