Rate-limited AniList client for discovery seeds (BL-0051)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/fixtures/anilist/title.json

@@ -0,0 +1,11 @@
+{"data":{"Media":{"id":101,"format":"MANGA","isAdult":false,
+  "title":{"romaji":"Tsuki no Tabibito","english":"Moon Traveller","native":"月の旅人"},
+  "synonyms":["Lunar Wanderer"],"status":"RELEASING","startDate":{"year":2019},
+  "averageScore":81,"popularity":5400,"trending":37,
+  "genres":["Adventure","Fantasy"],
+  "tags":[{"name":"Travel","rank":88,"isAdult":false},{"name":"Nudity","rank":40,"isAdult":true}],
+  "staff":{"edges":[
+    {"role":"Story & Art","node":{"id":900,"name":{"full":"Aoi Example"}}},
+    {"role":"Translator","node":{"id":901,"name":{"full":"Not An Author"}}}]},
+  "coverImage":{"extraLarge":"https://example.invalid/cover/101.jpg"},
+  "siteUrl":"https://anilist.co/manga/101"}}}