docs: add package comments to anime and episodes packages

internal/anime/service.go

@@ -1,3 +1,4 @@
+// Package anime provides anime catalog, discovery, search, and details services.
 package anime
 
 import (

internal/episodes/module.go

@@ -1,3 +1,4 @@
+// Package episodes manages episode availability checking and refresh scheduling.
 package episodes
 
 import (

internal/episodes/service/service.go

@@ -1,3 +1,4 @@
+// Package service provides episode availability checking logic.
 package service
 
 import (