Added has_cover_art query

No test cases yet.
Query to find albums with/without embedded cover art #2572

beets/library/models.py

@@ -805,6 +805,7 @@ class Item(LibModel):
         getters = plugins.item_field_getters()
         getters["singleton"] = lambda i: i.album_id is None
         getters["filesize"] = Item.try_filesize  # In bytes.
+        getters["has_images"] = Item.has_cover_art
         return getters
 
     def duplicates_query(self, fields: list[str]) -> dbcore.AndQuery:
@@ -1098,6 +1099,18 @@ class Item(LibModel):
             log.warning("could not get filesize: {}", exc)
             return 0
 
+    def has_cover_art(self):
+        """Check if item has embedded cover art.
+        
+        Return True if images embedded in file, False otherwise.
+        If file unreadable or no images, return False.
+        """
+        try:
+            mediafile = MediaFile(syspath(self.path))
+            return bool(mediafile.images)
+        except (UnreadableFileError, Exception):
+            return False
+
     # Model methods.
 
     def remove(self, delete=False, with_album=True):