docs(website): add player-not-provider disclaimer to TMDB guide

Matches the canonical disclaimer used across the site (README, footer,
other blog posts): IPTVnator is a pure player, provides no content, and
the feature only adds descriptive TMDB metadata on top of the user's own
library. Notes screenshots/posters are for demonstration only.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/website/src/content/blog/tmdb-metadata-guide.mdx

@@ -25,6 +25,15 @@ IPTVnator can fix that. With a free **TMDB** (The Movie Database) key, your Xtre
 
 It's **opt-in**, takes about two minutes to set up, and this guide walks through every step.
 
+<Alert type="info" title="IPTVnator is a player, not a content provider">
+    IPTVnator does not provide, sell, host, bundle, or redistribute any
+    playlists, channels, subscriptions, portals, or streams — it is only a
+    media player for sources **you** supply, and this feature only adds
+    descriptive metadata (from TMDB) on top of the titles already in your own
+    library. Please use it only with content you are authorized to access. The
+    screenshots and posters in this post are for demonstration purposes only.
+</Alert>
+
 ## What you get
 
 <IconFeatureGrid