Extend V3 metadata read support with encryption changes

[smaheshwar-pltr]

Feature Request / Improvement

The V3 spec changes for encryption have merged in apache/iceberg#12162. apache/iceberg#12927 has also merged, containing the resultant changes to table metadata on the Java side among other things.

Encryption changes table metadata by adding a encryption-keys field with this schema. It also changes metadata by adding key-id as an optional field to entries of the snapshots list - see https://iceberg.apache.org/spec/#snapshots.

This issue follows up to #1550 with encryption-related changes.