use new query helper

lib/policy_service_web/controllers/policy_controller.ex

@@ -9,38 +9,17 @@ defmodule PolicyServiceWeb.PolicyController do
   alias PolicyService.Commands.CarPolicy
 
   alias PolicyServiceWeb.Schemas.Policy, as: S
+  alias PolicyServiceWeb.QueryHelpers
 
   tags(["Policies"])
   security([%{"bearerAuth" => []}])
 
   operation(:index,
     summary: "List policies",
-    parameters: [
-      "page[number]": [in: :query, type: :integer, required: false],
-      "page[size]": [in: :query, type: :integer, required: false],
-      filters: [
-        in: :query,
-        required: false,
-        explode: true,
-        description: """
-        Apply filters in Flop format.
-
-        Example: filters[0][field]=status&filters[0][op]==&filters[0][value]=created
-        """,
-        schema: %{
-          type: :array,
-          items: %{
-            type: :object,
-            properties: %{
-              field: %{type: :string, description: "Field to filter on"},
-              op: %{type: :string, description: "Operator (e.g., ==, !=, ~>)"},
-              value: %{type: :string, description: "Filter value"}
-            }
-          }
-        }
-      ],
-      "order_by[]": [in: :query, type: :string, required: false]
-    ],
+    parameters: QueryHelpers.flop(
+      [:status, :policy_type, :search],
+      [:submitted_at, :policy_type, :status]
+    ),
     responses: [
       ok: {"Policy list", "application/json", S.PolicyListResponse},
       bad_request: {"Invalid params", "application/json", S.ErrorResponse}