Refactor Staff and Store models to use fromMap method; enhance StoreCubit with provider management functionality

lib/features/master_data/store/data/store_repository.dart

@@ -24,8 +24,16 @@ class StoreRepository {
           .from('store')
           .select('''
           *,
-          providers_count:providers_in_stores(count),
-          staff_members_count:staff_in_stores(count)
+          associated_providers:providers_in_stores (
+            provider (
+              *
+            )
+          )
+          associated_staff:staff_in_stores (
+            staff_member (
+              *
+            )
+          )
         ''')
           .eq('company_id', companyId)
           .order('nome');