[VL] Code clean up for Runtime API

Another refactor to remove unnecessary legacy polymorphism designs. The effort will include removing non-general code from `gluten-arrow` / `cpp/core` to `velox-backend` / `cpp/velox`, etc.

Review the legacy polymorphism designs and the referenced paths, starting with gluten-arrow/cpp/core and velox-backend/cpp/velox. Determine which non-general code is in scope and trace how the Runtime API uses it. Done means the unnecessary legacy designs and non-general code are removed across the identified areas.

Written by the indexing model from the issue text.