Implement `DFExtensionType` for Arrow's Canonical Extension Types

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

Now that it seems like we can merge https://github.com/apache/datafusion/pull/20312 soon, we should implement the full-range of Arrow's canonical extension types. Currently, only UUID is supported in the PR.

This issue tracks adding the remaining canonincal extension types:
- [x] Fixed shape tensor
- [x] Variable shape tensor
- [x] JSON
- [x] UUID
- [x] Opaque
- [x] 8-bit Boolean
- [ ] Parquet Variant
- [x] Timestamp With Offset

### Describe the solution you'd like

Implement the `DFExtensionType` similar to UUID.

The question that remains is how we implement pretty-printing for these types.
- Do we try to pretty-print tensors?
- Do we pretty-print JSON using newlines?
- I guess Parquet Variant would benefit from a nice representation in tests/CLIs. @friendlymatthew maybe you have some 2 cents here?

### Describe alternatives you've considered

We could implement the formatters within arrow-rs and just use them in DataFusion. But I am unsure where they best fit.

Maybe starting in DataFusion and migrating them to arrow-rs sometimes in the future (depending on a use case) is a good choice.

### Additional context

Some (maybe) related issues I've found:
- https://github.com/apache/datafusion/issues/7845
- https://github.com/apache/datafusion/issues/16116

Start by reviewing PR 20312 and the existing UUID implementation to understand how DFExtensionType is integrated. Then resolve the issue's open pretty-printing questions for the unchecked Parquet Variant type, with completion reflected in appropriate tests and CLI output.

Written by the indexing model from the issue text.