Track Iceberg v3 Feature Support (Roadmap for 0.4.0)

We already have **partial support for Iceberg v3** in the codebase (e.g., Row Lineage and partition statistics). However, a number of key v3 features are still missing.

This issue serves as a **parent tracking issue** for the remaining v3 work we plan to (partially) include in the **0.3.0 release**.

If you are interested in working on any of the items below, please **open a dedicated sub-issue** and link it back to this one.

## V3 related

### 1. Schema-Level Support for New v3 Types

Add support for all newly introduced v3 types at the schema level, including:

- [x] `timestamp_ns`, `timestamptz_ns` @zhjwpku
- [x] `unknown` @manuzhang
- [ ] `variant` @zhjwpku
- [x] `geometry`, `geography` @wgtmac

### 2. Column Default Values (Schema Evolution)

Enable schema evolution with default values:

- [x] Support `initial-default` and `write-default` @huan233usc
- [ ] Apply defaults correctly during read and write paths

### ~~3. Multi-Argument Transforms (Not planned, as they are not supported by the Java implementation)~~

### 4. Binary Deletion Vectors

Add support for deletion vectors (DV):

- [x] Puffin-based DV parsing @zhaoxuan1994

### 5. Table-Level Encryption Metadata (Not planned for 0.4.0) @shangxinli

Support encryption-related metadata defined in v3:

- [ ] Parse and preserve encryption metadata

### 6. Puffin-Based Statistics (Not planned for 0.4.0)

Support table and partition statistics stored in Puffin files:

- [ ] Metadata parsing
- [ ] Optional integration into scan planning

## Table update and maintenance: #364

- [x] OverwriteFiles @lishuxu
- [x] RowDelta @manuzhang
- [x] MergeAppend @zhjwpku
- [x] DeleteFiles @manuzhang
- [x] RewriteFiles @WZhuo
- [ ] ReplacePartitions @shangxinli
- [ ] RewriteManifests @zhjwpku
- [ ] CherryPickOperation @shangxinli

## Miscellaneous

- [ ] Metadata table inspection @All-less @WZhuo
- [x] LRU cache @HuaHuaY
- [ ] Logging interface and spdlog integration @kamcheungting-db

If anything is missing or you have suggestions, feel free to comment or open additional sub-issues.

Il s’agit d’une issue de suivi parente plutôt que d’une tâche autonome, et elle ne nomme aucun fichier, test ni point d’entrée. Choisissez un élément non coché, tel que les valeurs par défaut du schéma, les métadonnées de chiffrement ou une opération de mise à jour de table, puis ouvrez une sous-issue dédiée qui renvoie ici. Le travail est considéré comme terminé lorsque cet élément délimité est achevé et que l’entrée correspondante de la liste de contrôle est mise à jour.

Rédigé par le modèle d'indexation à partir du texte de l'issue.