feat: add discount management and PDF export for transmittals

- Create Discount model, migration, and Filament resource with relation to Client
- Add PDF export functionality for transmittals using DomPDF
- Include discount type selection in sales transactions
- Fix account filtering logic in expense resource
- Update export job to generate PDF instead of Excel

app/Filament/Resources/ExpenseResource.php

@@ -195,11 +195,11 @@ class ExpenseResource extends Resource
             'client_id' => $get('../../client'),
         ]);
 
-        if ($get('../../branch_id')) {
-            $query->whereHas('balances', function ($query) use ($get) {
-                return $query->where('branch_id', $get('../../branch_id'));
-            });
-        }
+        // if ($get('../../branch_id')) {
+        //     $query->whereHas('balances', function ($query) use ($get) {
+        //         return $query->where('branch_id', $get('../../branch_id'));
+        //     });
+        // }
 
         $query->whereHas('accountType', function ($query) {
             return $query->where('type', 'Expenses');
@@ -208,7 +208,6 @@ class ExpenseResource extends Resource
         return $query->get()->pluck('account', 'id');
     }
 
-    #[NoReturn]
     public static function setDefaultFormValues(Get $get, Set $set, ?string $old, ?string $state): void
     {