fix(merope/seerr): allow large Lidarr libraries

Raise the Axios response limit to 64 MiB only for Lidarr so large album libraries can complete SeerrNG scans without weakening the cap for other external APIs.

Assisted-by: pi (gpt-5.6-sol)

hosts/nixos/merope/services/media/jellyseerr.nix

@@ -18,6 +18,14 @@
       fetcherVersion = 3;
       hash = "sha256-xd+FrZDzUA/jLkWRrlL6K9r85/nNkYDR4jF/pObXomo=";
     };
+    postPatch =
+      (previousAttrs.postPatch or "")
+      + ''
+        substituteInPlace server/api/servarr/lidarr.ts \
+          --replace-fail \
+            "this.apiKey = apiKey;" \
+            "this.apiKey = apiKey; this.axios.defaults.maxContentLength = 64 * 1024 * 1024;"
+      '';
     meta =
       previousAttrs.meta
       // {