fix: adjustments to backup after end-to-end testing (#375)

This commit combines fixes for a number of issues that came up when
testing against real-world data:

- Assign timestamps to ZIP resources (folders and files):
  - Entity TOML files use the latest version timestamp
  - Other resources use the model timestamps
- Add new logic to define entity filenames:
  - Slugify all identifiers
  - Track all generated slugs
  - Use the slug directly if there is no naming conflict
  - If a conflict exists, fall back to a slugified hash of the key
- Add container children list to exported data.

Author: dwong2708

openedx_learning/apps/authoring/backup_restore/toml.py

@@ -12,7 +12,7 @@
 from openedx_learning.apps.authoring.publishing.models.learning_package import LearningPackage
 
 
-def toml_learning_package(learning_package: LearningPackage) -> str:
+def toml_learning_package(learning_package: LearningPackage, timestamp: datetime) -> str:
     """
     Create a TOML representation of the learning package.
 
@@ -27,7 +27,7 @@ def toml_learning_package(learning_package: LearningPackage) -> str:
         updated = 2025-09-03T17:50:59.536190Z
     """
     doc = tomlkit.document()
-    doc.add(tomlkit.comment(f"Datetime of the export: {datetime.now()}"))
+    doc.add(tomlkit.comment(f"Datetime of the export: {timestamp}"))
     section = tomlkit.table()
     section.add("title", learning_package.title)
     section.add("key", learning_package.key)
@@ -40,6 +40,8 @@ def toml_learning_package(learning_package: LearningPackage) -> str:
 
 def _get_toml_publishable_entity_table(
         entity: PublishableEntity,
+        draft_version: PublishableEntityVersion | None,
+        published_version: PublishableEntityVersion | None,
         include_versions: bool = True) -> tomlkit.items.Table:
     """
     Create a TOML representation of a publishable entity.
@@ -64,28 +66,30 @@ def _get_toml_publishable_entity_table(
     entity_table.add("can_stand_alone", entity.can_stand_alone)
     # Add key since the toml filename doesn't show the real key
     entity_table.add("key", entity.key)
+    entity_table.add("created", entity.created)
 
     if not include_versions:
         return entity_table
 
-    current_draft_version = publishing_api.get_draft_version(entity)
-    current_published_version = publishing_api.get_published_version(entity)
-
-    if current_draft_version:
+    if draft_version:
         draft_table = tomlkit.table()
-        draft_table.add("version_num", current_draft_version.version_num)
+        draft_table.add("version_num", draft_version.version_num)
         entity_table.add("draft", draft_table)
 
     published_table = tomlkit.table()
-    if current_published_version:
-        published_table.add("version_num", current_published_version.version_num)
+    if published_version:
+        published_table.add("version_num", published_version.version_num)
     else:
         published_table.add(tomlkit.comment("unpublished: no published_version_num"))
     entity_table.add("published", published_table)
     return entity_table
 
 
-def toml_publishable_entity(entity: PublishableEntity, versions_to_write: list[PublishableEntityVersion]) -> str:
+def toml_publishable_entity(
+        entity: PublishableEntity,
+        versions_to_write: list[PublishableEntityVersion],
+        draft_version: PublishableEntityVersion | None,
+        published_version: PublishableEntityVersion | None) -> str:
     """
     Create a TOML representation of a publishable entity and its versions.
 
@@ -114,7 +118,7 @@ def toml_publishable_entity(entity: PublishableEntity, versions_to_write: list[P
         [version.container.unit]
         graded = true
     """
-    entity_table = _get_toml_publishable_entity_table(entity)
+    entity_table = _get_toml_publishable_entity_table(entity, draft_version, published_version)
     doc = tomlkit.document()
     doc.add("entity", entity_table)
     doc.add(tomlkit.nl())
@@ -152,16 +156,22 @@ def toml_publishable_entity_version(version: PublishableEntityVersion) -> tomlki
     version_table.add("title", version.title)
     version_table.add("uuid", str(version.uuid))
     version_table.add("version_num", version.version_num)
+
     container_table = tomlkit.table()
-    container_table.add("children", [])
+
+    children = []
+    if hasattr(version, 'containerversion'):
+        children = publishing_api.get_container_children_entities_keys(version.containerversion)
+    container_table.add("children", children)
+
     unit_table = tomlkit.table()
-    unit_table.add("graded", True)
+
     container_table.add("unit", unit_table)
     version_table.add("container", container_table)
     return version_table  # For use in AoT
 
 
-def toml_collection(collection: Collection) -> str:
+def toml_collection(collection: Collection, entity_keys: list[str]) -> str:
     """
     Create a TOML representation of a collection.
 
@@ -178,7 +188,6 @@ def toml_collection(collection: Collection) -> str:
     """
     doc = tomlkit.document()
 
-    entity_keys = collection.entities.order_by("key").values_list("key", flat=True)
     entities_array = tomlkit.array()
     entities_array.extend(entity_keys)
     entities_array.multiline(True)