fix: use _request() in delete_bom_entry() for consistent error handling (#59)

delete_bom_entry() used raw urllib.request instead of self._request(),
bypassing 401 auth clearing and standard error normalization. Replace
with a single _request('DELETE', ..., raw=True) call, matching the
pattern used by all other BOM methods.

silo_client/__init__.py

@@ -844,16 +844,7 @@ class SiloClient:
     def delete_bom_entry(self, parent_pn: str, child_pn: str) -> None:
         ppn = urllib.parse.quote(parent_pn, safe="")
         cpn = urllib.parse.quote(child_pn, safe="")
-        url = f"{self.base_url}/items/{ppn}/bom/{cpn}"
-        headers = {"Content-Type": "application/json"}
-        headers.update(self._auth_headers())
-        req = urllib.request.Request(url, headers=headers, method="DELETE")
-        try:
-            urllib.request.urlopen(req, context=self._ssl_context())
-        except urllib.error.HTTPError as e:
-            raise RuntimeError(f"API error {e.code}: {e.read().decode()}")
-        except urllib.error.URLError as e:
-            raise RuntimeError(f"Connection error: {e.reason}")
+        self._request("DELETE", f"/items/{ppn}/bom/{cpn}", raw=True)
 
     # -- Schemas ------------------------------------------------------------