fix: handle malformed Gitea collections (#99)

src/main.py

@@ -81,6 +81,11 @@ async def context() -> JSONResponse:
             raise ValueError("Gitea current-user response was not an object")
         if not all(field in user_data for field in ("id", "login")):
             raise ValueError("Gitea current-user response did not include id and login")
+        if any(
+            data is not None and not isinstance(data, list)
+            for data in (repo_data, issues_data, prs_data)
+        ):
+            raise ValueError("Gitea collection response was not a list")
     except Exception as e:
         error_message = (
             f"Gitea context request timed out after {CONTEXT_TIMEOUT_SECONDS:g}s"