feat: add kefintweaks watchlist integration properly

components/AddToKefinWatchlist.tsx

@@ -0,0 +1,28 @@
+import type { BaseItemDto } from "@jellyfin/sdk/lib/generated-client";
+import type { FC } from "react";
+import { View, type ViewProps } from "react-native";
+import { RoundButton } from "@/components/RoundButton";
+import { useWatchlist } from "@/hooks/useWatchlist";
+
+interface Props extends ViewProps {
+  item: BaseItemDto;
+}
+
+/**
+ * KefinTweaks watchlist toggle, backed by Jellyfin's "Likes" rating.
+ * Render only when settings.useKefinTweaks is enabled.
+ */
+export const AddToKefinWatchlist: FC<Props> = ({ item, ...props }) => {
+  const { isWatchlisted, toggleWatchlist } = useWatchlist(item);
+
+  return (
+    <View {...props}>
+      <RoundButton
+        size='large'
+        icon={isWatchlisted ? "bookmark" : "bookmark-outline"}
+        color={isWatchlisted ? "purple" : "white"}
+        onPress={toggleWatchlist}
+      />
+    </View>
+  );
+};