Prefer local snapshot over web archive link in bookmark list links (#1021)

* Prefer local snapshot over web archive link

* Update latest snapshot when it is deleted

* fix filter in migration

* improve migration performance

bookmarks/migrations/0044_bookmark_latest_snapshot.py

@@ -0,0 +1,46 @@
+# Generated by Django 5.1.7 on 2025-03-22 12:28
+
+import django.db.models.deletion
+from django.db import migrations, models
+from django.db.models import OuterRef, Subquery
+
+
+def forwards(apps, schema_editor):
+    # Update the latest snapshot for each bookmark
+    Bookmark = apps.get_model("bookmarks", "bookmark")
+    BookmarkAsset = apps.get_model("bookmarks", "bookmarkasset")
+
+    latest_snapshots = (
+        BookmarkAsset.objects.filter(
+            bookmark=OuterRef("pk"), asset_type="snapshot", status="complete"
+        )
+        .order_by("-date_created")
+        .values("id")[:1]
+    )
+    Bookmark.objects.update(latest_snapshot_id=Subquery(latest_snapshots))
+
+
+def reverse(apps, schema_editor):
+    pass
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bookmarks", "0043_userprofile_collapse_side_panel"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="bookmark",
+            name="latest_snapshot",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="latest_snapshot",
+                to="bookmarks.bookmarkasset",
+            ),
+        ),
+        migrations.RunPython(forwards, reverse),
+    ]