fix: Grid column respects custom reversed comparator and improves serialization (#3926)

[Artur-]

• Store the original Comparator object instead of just method references
• Preserve SerializableComparator instances when provided
• Respect custom reversed() implementations for descending sort

The column now stores the full comparator object, allowing it to:

1. Use custom reversed() implementations when sorting descending
2. Preserve serialization capability when SerializableComparator is provided
3. Only create method references as a fallback for non-serializable comparators

Fixes #3926

[Artur-]

The API seems to be a lie as there is setComparator(Comparator<T> comparator) but SerializableComparator<T> getComparator( SortDirection sortDirection) which does not in any way ensure the comparator is serializable

[sissbruecker]

It looks like the change breaks serialization:

java.lang.RuntimeException: serializeAndDeserializeUi_noExceptionIsThrown[any_Chrome_](com.vaadin.flow.component.grid.it.GridLitRendererSerializationIT)

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

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