feat: create route to handle updating watch status in AniList

src/mocks/anilist/updateWatchStatus.ts

@@ -0,0 +1,37 @@
+import { HttpResponse, graphql } from "msw";
+
+export function updateAnilistWatchStatus() {
+  return graphql.mutation(
+    "UpdateWatchStatus",
+    ({ variables: { titleId, watchStatus }, request: { headers } }) => {
+      console.log(
+        `Intercepting UpdateWatchStatus mutation with ID ${titleId}, watch status ${watchStatus} and Authorization header ${headers.get("authorization")}`,
+      );
+
+      if (titleId === -1) {
+        return HttpResponse.json({
+          errors: [
+            {
+              message: "validation",
+              status: 400,
+              locations: [
+                {
+                  line: 2,
+                  column: 2,
+                },
+              ],
+              validation: {
+                mediaId: ["The selected media id is invalid."],
+              },
+            },
+          ],
+          data: {
+            SaveMediaListEntry: null,
+          },
+        });
+      }
+
+      return HttpResponse.json({ data: { id: titleId } });
+    },
+  );
+}