重构 Config

[Glavo]

本 PR

1. 重新排序了 Config 的字段，使未来我们添加字段更容易；
2. 重新实现了 Config 的序列化
   1. 现在 Config 仅会序列化被修改过的字段，不会将字段默认值写入配置文件，以便我们未来调整这些字段的默认值。
   2. 现在 Config 在反序列化时会保存所有未知字段，避免旧版本 HMCL 损坏新版本 HMCL 的配置文件

[Copilot]

Pull Request Overview

This PR refactors the Config class to improve field organization, implement selective serialization, and preserve unknown fields for backward compatibility.

• Reorganizes Config fields with better logical grouping and organization
• Implements selective serialization that only writes modified fields to avoid storing default values
• Adds support for preserving unknown fields during deserialization to prevent config corruption between different HMCL versions

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
DirtyTracker.java	New utility for tracking which Observable properties have been modified
ObservableField.java	New reflection-based utility for handling JavaFX Observable properties with Gson serialization
TypeUtils.java	Utility class copied from Gson for advanced type resolution and manipulation
Config.java	Major refactoring with field reorganization, custom adapter for selective serialization, and unknown field preservation

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[Copilot]

This logic doesn't handle fields with alternate names defined by @SerializedName annotation. The code only checks for the primary serialized name but ignores the alternate names, which could cause deserialization to fail for fields using alternate names.