Sanity check readability of tables with variant field in other engines

### Task Description

**What needs to be done:**

Sanity check readability of tables with variant field in other engines
https://github.com/apache/hudi/pull/17833#pullrequestreview-3971914696

Engines include:
1. trino
2. presto
3. hudi-rs

**Why this task is needed:**

### Task Type

Code improvement/refactoring

### Related Issues

**Parent feature issue:** (if applicable )
**Related issues:**
NOTE: Use `Relationships` button to add parent/blocking issues after issue is created.

Start by reading the linked pull request review at apache/hudi#17833 to understand the variant-field table changes. Check readability in the three named engines—Trino, Presto, and hudi-rs—and determine what evidence is needed to consider the cross-engine sanity check complete.

Written by the indexing model from the issue text.