Correct Delta protocol terminology "enabled" vs "supported"

## Description

This PR fixes a terminology issue in Delta protocol, so the term `supported` is now used to describe a table feature name being listed in table protocol's `readerFeatures` and/or `writerFeatures`. The choice of this word is to emphasize that, in such a scenario, the Delta table *may* use the listed table features but is not forced to do so.

For example, when `appendOnly` is listed in a table's protocol, the table may or may not be append-only, depending on the existence and value of table property `delta.appendOnly`. However, writers must recognize the table feature `appendOnly` and know that the table property should be checked before writing this table.

This PR did not touch the Row ID/Row Tracking sections, as it's handled by another PR: #1747.

Closes #1780

Co-authored-by: Lars Kroll <lars.kroll@databricks.com>
Co-authored-by: Bart Samwel <bart.samwel@databricks.com>
Signed-off-by: Paddy Xu <xupaddy@gmail.com>
GitOrigin-RevId: 8d9b86262e91a88a85388c6333c5ef7ac296931e