Add voucher-line party (تفصیل) and allow cache-control CORS headers.

Supports accounting journal detail parties and preflight from the Vite client that sends Cache-Control/Pragma.

Co-authored-by: Cursor <cursoragent@cursor.com>

accounting/migrations/0011_voucherline_party.py

@@ -0,0 +1,23 @@
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('accounting', '0010_voucher_regarding_invoiceline_event_name'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='voucherline',
+            name='party',
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name='voucher_lines',
+                to='accounting.party',
+            ),
+        ),
+    ]