Fuzz underlying physical types for logical types in sqllogictests

### Is your feature request related to a problem or challenge?

If we have a function that accepts a string argument, this could be provided as `Utf8`, `LargeUtf8`, `Utf8View`, or via a `Dictionary` type; In SLT tests we would have to ensure we cover all these input types to ensure we don't accidentally miss an implementation.

### Describe the solution you'd like

Have a way in our SLT tests to fuzz the physical types of logical types; this extends to lists (`List`, `LargeList`, `FixedSizeList`) and other types too. Would need to consider tests which check the output type as well since those could be dependent on the input type.

### Describe alternatives you've considered

_No response_

### Additional context

Spawned from comment here: https://github.com/apache/datafusion/issues/13408#issuecomment-3368478752

Start by reviewing the existing sqllogictests (SLT) and the discussion linked from issue #13408. Define how logical types such as strings and lists can exercise their physical variants, including Dictionary types, and identify how output-type assertions should behave when inputs vary. Done means SLT coverage can fuzz these physical representations without invalidating intentional output checks.

Written by the indexing model from the issue text.