feat(reactor): Add support for Brotli compressed resources

[YagUber]

Adds Brotli support for encrypted .NET Reactor resources.

The resolver previously treated the decrypted payload as either a raw PE, QuickLZ data, or deflate data. My sample’s resource initializer uses BrotliStream(..., Decompress), so none of those paths produced the embedded managed resource.

The resolver now yields raw, QuickLZ, deflate, and Brotli candidates, then accepts the first one dnlib can load as a managed module. Decoder failures are now treated as failed candidates, allowing the remaining formats to be tested. This also removes the old 64 byte/raw header heuristic. The final candidate is now validated by dnlib rather than by header check alone.

.NET Framework 4.8 does not provide System.IO.Compression.BrotliStream, so the change adds a conditional BrotliSharpLib dependency for .NET Framework builds.

[meck-gd]

Thanks!