Add ACE archive support (read-only, stored entries)

[Copilot]

Adds support for reading ACE archives (version 1.0 and 2.0 formats) as requested in #875. Due to the proprietary nature of ACE compression algorithms, only stored (uncompressed) entries can be extracted.

Changes

• New types: AceReader, AceEntry, AceEntryHeader, AceFilePart, AceVolume, AceFactory
• ArchiveType enum: Added Ace value
• CompressionType enum: Added Ace and Ace2 values for ACE 1.0 and 2.0 compression
• Factory registration: AceFactory registered for automatic format detection via **ACE** signature at offset 7
• ACE 2.0 support: Main header parsing for version detection, host OS, solid/multi-volume flags, and recovery record header handling

Usage

using var stream = File.OpenRead("archive.ace");
using var reader = AceReader.Open(stream);

while (reader.MoveToNextEntry())
{
    if (!reader.Entry.IsDirectory)
    {
        reader.WriteEntryToDirectory("output/", new ExtractionOptions { ExtractFullPath = true });
    }
}

Limitations

• Read-only (no write support)

• Only stored/uncompressed entries extractable

• Compressed entries (ACE LZ77 and ACE 2.0 improved LZ77) throw NotSupportedException due to proprietary algorithms

• No Archive API (reader-only, like Arj)

• Fixes [Feature Request] ACE archive support #875

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Feature Request] ACE archive support</issue_title>
<issue_description>ACE archive support would be nice, especially for version 1 archives as that seems to be better documented. The ArchiveTeam wiki has good resources for ACE archives, including a link to example files and software that is able to extract it. http://fileformats.archiveteam.org/wiki/ACE</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [Feature Request] ACE archive support #875

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[adamhathcock]

@copilot add ACE 2.0 format reading

[Copilot]

@copilot add ACE 2.0 format reading

Added ACE 2.0 format reading support in commit f796aa1. Changes include:

• Main header now parses ACE version (10=1.0, 20=2.0), host OS, solid/multi-volume flags
• Recovery record headers (ACE 2.0 feature) are properly skipped
• Added dedicated Ace and Ace2 compression types
• Updated documentation to reflect both versions

Note: Extraction of compressed entries is still not supported since both ACE 1.0 LZ77 and ACE 2.0 improved LZ77 are proprietary algorithms without public documentation.