Fix BYTES primary key columns in dimension tables can never be looked up

[waterWang]

Fix a bug where dimension tables with a BYTES primary key column can never be looked up.

Root cause: DimensionTableDataManager stores raw byte[] in the Object[] key array, but byte[] inherits identity-based hashCode/equals from Object. The probe side (LookupTransformFunction) correctly wraps the value in ByteArray (content-based), but it never matches the stored byte[].

Fix: Wrap byte[] values as ByteArray in both createFastLookupDimensionTable and the memory-optimized path, so the stored key has content-based equality.

Fixes #19228