Tracking issues to make iceberg-rust more friendly to Rust users

This issue is used to track issues to make iceberg-rust more friendly to Rust users.

## Context

> Iceberg-rust itself feels too much like Java.
>
> It’s partly the history of how iceberg-rust was decided. The early core group of contributors consisted of two kinds of people: one group familiar with Iceberg but not yet experienced in Rust, who wanted to learn Rust by contributing to iceberg-rust; the other group familiar with Rust but knowing very little about Iceberg, who wanted to learn more about Iceberg through contribution.
>
> So in either case, following the same pattern from Java wasn’t a bad option. Otherwise, we wouldn’t have been able to build iceberg-rust into its current shape.
>
> The other reason, as @Twuebi and @liurenjie1024 mentioned, is that although Iceberg has a great spec and the spec intends to be language-agnostic and allow different languages to have their own implementations, that never truly happened. In reality, many things aren’t defined or clearly spelled out in the Iceberg spec, so we have to refer to Iceberg-Java’s current behavior to make things work.
>
> I’m not here to defend ourselves. It’s just the reality we’re facing. To improve in this area, we need to find a way to make our implementation correct and gradually improve it to be more friendly to Rust users.

## Tasks

Please provide your feedback here.

Start by reading the context and reviewing the existing discussion for concrete examples of where iceberg-rust feels too much like Java. No files, tests, or entry points are identified, so research must first turn feedback into specific follow-up tasks; this tracker is done only when actionable tasks and their scope are recorded.

Written by the indexing model from the issue text.