Fix Iris parser httpx read timeout for file uploads (#524)

The httpx.AsyncClient was created without a timeout parameter,
defaulting to 5 seconds for reads. This is too short for uploading
PDFs to presigned URLs and waiting for Iris API responses. Set
explicit timeouts: 30s default, 120s for reads.

Author: cdbartholomew

hindsight-api/hindsight_api/engine/parsers/iris.py

@@ -62,7 +62,7 @@ async def convert(self, file_data: bytes, filename: str) -> str:
         """
         content_type = mimetypes.guess_type(filename)[0] or "application/octet-stream"
 
-        async with httpx.AsyncClient() as client:
+        async with httpx.AsyncClient(timeout=httpx.Timeout(30.0, read=120.0)) as client:
             # Step 1: Request a presigned upload URL
             init_resp = await client.post(
                 f"{_IRIS_BASE_URL}/org/{self._org_id}/files",