docs: use new x-sidebar-summary for sidebar items in api-reference if available (#8865)

Use the new `x-sidebar-summary` OAS attribute when adding operations to the sidebar, if available.

www/apps/api-reference/types/openapi.ts

@@ -19,6 +19,7 @@ export type Operation = OpenAPIV3.OperationObject<{
   parameters: Parameter[]
   "x-featureFlag"?: string
   "x-workflow"?: string
+  "x-sidebar-summary"?: string
 }>
 
 export type RequestObject = OpenAPIV3.RequestBodyObject & {

www/apps/api-reference/utils/get-tag-child-sidebar-items.tsx

@@ -23,7 +23,10 @@ export default function getTagChildSidebarItems(
           ...(definedOperation.tags || []),
           definedOperation.operationId,
         ]),
-        title: definedOperation.summary || definedOperation.operationId,
+        title:
+          definedOperation["x-sidebar-summary"] ||
+          definedOperation.summary ||
+          definedOperation.operationId,
         additionalElms: (
           <MethodLabel method={definedMethod} className="h-fit" />
         ),