Stop sending the redundant per_page parameter on every list request

frontend/src/api/index.js

@@ -16,10 +16,18 @@ api.interceptors.request.use(config => {
   if (token) {
     config.headers.Authorization = `Bearer ${token}`
   }
-  // Send both perpage and per_page for backend compatibility
-  if (config.params?.perpage) {
-    config.params.per_page = config.params.perpage
-  }
+  // `per_page` used to be sent alongside `perpage` for backend compatibility.
+  // get_pagination_params reads `perpage` and only falls back to `per_page`, and
+  // this client always sends `perpage`, so the duplicate never did anything -
+  // it just made every list URL carry a redundant parameter.
+  //
+  // Dropping it also has a one-off benefit worth recording. The endpoints list
+  // route used to redirect (308, PERMANENT and therefore cached by the browser
+  // against the exact URL including its query string). Clients that hit the old
+  // route hold that rewrite even after the server is fixed: the request never
+  // leaves the machine, so nothing deployed can clear it. Changing the query
+  // string changes the cache key, so those clients miss the poisoned entry and
+  // reach the corrected route.
   return config
 })