Apply suggestions from code review

Co-authored-by: Copilot <[email protected]>

Author: pamelafox

app/backend/prepdocslib/blobmanager.py

@@ -432,7 +432,8 @@ async def upload_blob(self, file: File) -> str:
                 blob_client = await container_client.upload_blob(blob_name, reopened_file, overwrite=True)
                 file.url = blob_client.url
 
-        assert file.url is not None, "file.url must be set after upload"
+        if file.url is None:
+            raise ValueError("file.url must be set after upload")
         return unquote(file.url)
 
     async def upload_document_image(

app/backend/prepdocslib/page.py

@@ -67,7 +67,7 @@ def from_skill_payload(cls, data: dict[str, Any]) -> tuple["ImageOnPage", str]:
         if filename is None:
             raise ValueError("filename is required")
         if figure_id is None:
-            raise ValueError("figure_id is required")
+            raise ValueError("figure_id is required for ImageOnPage deserialization")
 
         # Generate placeholder if not provided
         if placeholder is None:

tests/test_searchmanager.py

@@ -694,7 +694,7 @@ async def mock_upload_documents(self, documents):
         description="Test image",
         figure_id="fig1",
         page_num=0,
-        placeholder="<figure id='fig1'></figure>",  # required positional arg
+        placeholder="<figure id='fig1'></figure>",
         url="http://example.com/img1.png",
         embedding=[0.01, 0.02],
     )