Arithmetic type coercion fails for RunEndEncoded columns

[asubiotto]

Describe the bug

#18561 added REE type coercion but missed the arithmetic path. Arithmetic operations on RunEndEncoded columns fail during planning with:

Cannot coerce arithmetic expression RunEndEncoded("run_ends": non-null Int32, "values": non-null Int64) + Int64 to valid types

To Reproduce

Attempt any arithmetic expression involving a RunEndEncoded column, e.g. ree_col + 1 where ree_col is RunEndEncoded<Int32, Int64>.

Expected behavior

Arithmetic coercion should unwrap the REE value type, matching Dictionary behavior.