feat: moneda y tipo de cambio del documento (debajo del Nº de referencia) y ajustes de moneda local de la empresa

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

apps/web/src/app/features/documents/document-form.page.html

@@ -248,6 +248,25 @@
         }
       </div>
     }
+    @case ('currency') {
+      <sbo-field [label]="f.label">
+        <sbo-select
+          width="170px"
+          ariaLabel="Moneda del documento"
+          [options]="currencyOptions()"
+          [readonly]="readOnly() || locked(f)"
+          [value]="currencyValue()"
+          (valueChange)="onCurrency('' + ($event ?? ''))"
+        />
+        <sbo-number
+          ariaLabel="Tipo de cambio"
+          [decimals]="6"
+          [readonly]="readOnly() || locked(f) || isLocalCurrency()"
+          [value]="isLocalCurrency() ? null : +str(header()['DocRate'])"
+          (valueChange)="setHeader('DocRate', $event ?? '')"
+        />
+      </sbo-field>
+    }
     @case ('rounding') {
       @if (roundingEnabled()) {
         <sbo-field [label]="f.label">