fix(backend): preserve original filename in chunk metadata instead of temp file name

When uploading files, the backend passes them through NamedTemporaryFile, causing os.path.basename to return temp names like 'tmp90i7xqa8.pdf'. Added original_filename parameter to extract_metadata() so the actual upload filename is stored.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

backend/app/routers/ingest.py

@@ -59,7 +59,7 @@ async def ingest_document(file: UploadFile = File(...)):
         if not chunks:
             raise HTTPException(status_code=400, detail="Document appears to be empty or could not be parsed")
 
-        metadata = extract_metadata(temp_path, chunks)
+        metadata = extract_metadata(temp_path, chunks, original_filename=filename)
 
         rag = RAGService(settings=settings)
         document_id = rag.ingest_document(temp_path, chunks, metadata)

backend/app/utils/metadata.py

@@ -5,11 +5,11 @@ from datetime import datetime
 from typing import List, Dict, Any
 
 
-def extract_metadata(file_path: str, chunks: List[str]) -> List[Dict[str, Any]]:
+def extract_metadata(file_path: str, chunks: List[str], original_filename: str | None = None) -> List[Dict[str, Any]]:
     """Extract metadata for a list of text chunks.
 
     For each chunk, create a metadata dictionary containing:
-    - filename: basename of the provided file_path
+    - filename: basename of the provided file_path (or original_filename if provided)
     - upload_date: ISO 8601 timestamp of when metadata was generated
     - content_summary: first 200 characters of the chunk (or full chunk if shorter)
     - chunk_index: 0-based index of the chunk
@@ -17,6 +17,8 @@ def extract_metadata(file_path: str, chunks: List[str]) -> List[Dict[str, Any]]:
     Args:
         file_path: Path to the file associated with the chunks.
         chunks: List of string chunks to generate metadata for.
+        original_filename: Override filename stored in metadata when file_path
+            is a temp file.
 
     Returns:
         A list of metadata dictionaries, one per chunk. If chunks is empty, returns an empty list.
@@ -33,7 +35,7 @@ def extract_metadata(file_path: str, chunks: List[str]) -> List[Dict[str, Any]]:
     if not os.path.exists(file_path):
         raise FileNotFoundError(f"File not found: {file_path}")
 
-    filename = os.path.basename(file_path)
+    filename = original_filename if original_filename else os.path.basename(file_path)
     upload_date = datetime.now().isoformat()
 
     metadata: List[Dict[str, Any]] = []