移除 Pack200 支持

[Glavo]

目前 HMCL 不再兼容 Java 8，用户所用的 Java 支持 Pack200 的可能性大大降低，继续保留对 Pack200 的支持缺乏意义，所以让我们彻底移除这部分代码。

[Copilot]

Pull Request Overview

This PR removes Pack200 support from HMCL as the application no longer supports Java 8, making Pack200 compatibility unnecessary since newer Java versions have deprecated or removed Pack200 functionality.

• Completely removes the Pack200Utils utility class
• Updates RemoteVersion to remove Pack200-related download logic and types
• Removes Pack200 decompression handling from HMCLDownloadTask
• Removes Pack200-related classpath entry from build configuration

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
HMCLCore/src/main/java/org/jackhuang/hmcl/util/Pack200Utils.java	Complete removal of Pack200 utility class
HMCL/src/main/java/org/jackhuang/hmcl/upgrade/RemoteVersion.java	Removes Pack200 download option and PACK_XZ type enum
HMCL/src/main/java/org/jackhuang/hmcl/upgrade/HMCLDownloadTask.java	Removes Pack200 decompression logic and XZ dependencies
HMCL/build.gradle.kts	Removes pack200.jar from classpath configuration

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