perf: exclude unused fields from ItemDTO list and WebSocket serialization

Every item_updated WebSocket event and every history/queue list response
was serializing the full ItemDTO including fields the UI never reads.

Add ItemDTO.serialize_for_list() which excludes: options,
template_chapter, temp_dir, total_bytes, total_bytes_estimate,
tmpfilename, archive_id. The global Encoder now uses serialize_for_list()
for all list/event contexts; the full serialize() remains available for
detail endpoints (GET /api/history/{id}).

Mark the excluded fields optional in the TypeScript StoreItem type.

app/library/ItemDTO.py

@@ -661,6 +661,39 @@ class ItemDTO:
             "_archive_file",
         )
 
+    @staticmethod
+    def list_excluded_fields() -> tuple:
+        """
+        Fields excluded from list and WebSocket serialization as they are not used by the UI.
+
+        Returns:
+            tuple: A tuple of field names to exclude from list/event responses.
+
+        """
+        return (
+            "options",
+            "template_chapter",
+            "temp_dir",
+            "total_bytes",
+            "total_bytes_estimate",
+            "tmpfilename",
+            "archive_id",
+        )
+
+    def serialize_for_list(self) -> dict:
+        """
+        Serialize the item to a dictionary, excluding fields not needed for list/WebSocket payloads.
+
+        Returns:
+            dict: The serialized item with list-unused fields removed.
+
+        """
+        if "finished" == self.status and not self._recomputed:
+            self.archive_status()
+
+        item, _ = clean_item(self.__dict__.copy(), ItemDTO.removed_fields() + ItemDTO.list_excluded_fields())
+        return item
+
     def __post_init__(self):
         """
         Post-initialization to compute archive status if applicable.

app/library/encoder.py

@@ -23,7 +23,7 @@ class Encoder(json.JSONEncoder):
             return str(o)
 
         if isinstance(o, ItemDTO):
-            return o.serialize()
+            return o.serialize_for_list()
 
         if isinstance(o, object):
             if hasattr(o, "serialize"):

app/tests/test_itemdto.py

@@ -425,3 +425,32 @@ class TestItemAddExtras:
         assert item.extras["boolean"] is True
         assert item.extras["list"] == [1, 2, 3]
         assert item.extras["dict"] == {"nested": "data"}
+
+
+@pytest.fixture
+def sample_item() -> ItemDTO:
+    with patch.object(ItemDTO, "__post_init__", lambda _: None):
+        return ItemDTO(id="test", title="Test Video", url="http://example.com/test", folder="/downloads")
+
+
+class TestSerializeForList:
+    def test_excludes_listed_fields(self, sample_item: ItemDTO) -> None:
+        result = sample_item.serialize_for_list()
+        for field in ItemDTO.list_excluded_fields():
+            assert field not in result, f"Field '{field}' should be excluded from serialize_for_list"
+
+    def test_includes_required_ui_fields(self, sample_item: ItemDTO) -> None:
+        result = sample_item.serialize_for_list()
+        for field in ("_id", "url", "title", "status", "download_dir"):
+            assert field in result, f"Field '{field}' should be present in serialize_for_list"
+
+    def test_list_excluded_fields_is_tuple(self) -> None:
+        assert isinstance(ItemDTO.list_excluded_fields(), tuple)
+
+    def test_serialize_for_list_is_subset_of_serialize(self, sample_item: ItemDTO) -> None:
+        full = sample_item.serialize()
+        slim = sample_item.serialize_for_list()
+        for key in slim:
+            assert key in full, f"serialize_for_list key '{key}' not found in full serialize"
+        for excluded in ItemDTO.list_excluded_fields():
+            assert excluded not in slim

ui/app/types/store.d.ts

@@ -39,7 +39,7 @@ type StoreItem = {
   /** Download directory */
   download_dir: string;
   /** Temporary directory for the item */
-  temp_dir: string;
+  temp_dir?: string;
   /** Status of the item */
   status: ItemStatus;
   /** If the item has cookies */
@@ -47,7 +47,7 @@ type StoreItem = {
   /** If the item has custom output_template */
   template: string;
   /** If the item has custom output_template for chapters */
-  template_chapter: string;
+  template_chapter?: string;
   /** When the item was created */
   timestamp: number;
   /** If the item is a live stream */
@@ -63,7 +63,7 @@ type StoreItem = {
   /** If the item is auto-started */
   auto_start: boolean;
   /** Options for the item */
-  options: Record<string, unknown>;
+  options?: Record<string, unknown>;
   /** Sidecar associated with the item. */
   sidecar: {
     Unknown?: Array<SideCar>;