Support Array type in KV table

### Search before asking

- [x] I searched in the [issues](https://github.com/apache/fluss/issues) and found nothing similar.

### Motivation

Add Array type support for KV table scenarios to enable primary key tables with array columns.

### Solution

- Extend KV table storage format to support Array type
- Implement Array type serialization/deserialization for KV tables
- Add support for Array type in KV table read/write operations

### Anything else?

_No response_

### Willingness to contribute

- [ ] I'm willing to submit a PR!

Start by locating the KV table storage format and the existing type serialization/deserialization and read/write paths. Compare how current column types are handled, then verify that primary key KV tables with array columns can be stored, read, and written successfully.

Written by the indexing model from the issue text.