[release/3.6] 移除 Pack200 支持

[Glavo]

#4267

[Copilot]

Pull Request Overview

This pull request removes Pack200 support from the HMCL project. Pack200 was a Java compression format that has been deprecated and removed from modern Java versions.

• Removes the entire Pack200Utils utility class
• Updates RemoteVersion to only support JAR downloads, removing Pack200/XZ support
• Simplifies HMCLDownloadTask by removing Pack200 decompression logic
• 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	Simplified to only support JAR downloads, removed Pack200 logic
HMCL/src/main/java/org/jackhuang/hmcl/upgrade/HMCLDownloadTask.java	Removed Pack200 decompression handling
HMCL/build.gradle.kts	Removed Pack200 classpath entry from manifest

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