Wire REE field name constants to more usages in arrow-schema

`Field::REE_RUN_ENDS_FIELD_DEFAULT_NAME` and `Field::REE_VALUES_FIELD_DEFAULT_NAME` were added to improve REE display/parse. There are likely places that still hard-code "run_ends" and "values" strings when constructing or matching REE fields, similar to how `MAP_KEYS_FIELD_DEFAULT_NAME` / `MAP_VALUE_FIELD_DEFAULT_NAME` are used for Map types. The goal is to consolidate to these constants as the single source of truth.

"in a followup PR we can wire this in to more places where its used, similar to the map consts above"

_Originally posted by @Jefffrey in https://github.com/apache/arrow-rs/pull/10840#discussion_r3963485896_

Start in the arrow-schema code by searching for hard-coded "run_ends" and "values" strings used with REE fields, then compare those usages with the Map field constant patterns. Replace the relevant construction and matching references with Field::REE_RUN_ENDS_FIELD_DEFAULT_NAME and Field::REE_VALUES_FIELD_DEFAULT_NAME; done means those constants are the single source of truth and the existing tests pass.

Written by the indexing model from the issue text.