.NET 9 upgrade

Merge pull request #31 from Open-NET-Libraries/v7

For Channels v7

Merge pull request #30 from Open-NET-Libraries/v6

V6

Fixed infinite recursion.

Corrected behavior so that a buffered channel reader doesn't fill up …

…by default.

Updated readme.

Updated gitignore.

Updated references. Added snugpk.

Improved exception handling for concurrent methods.

Final touches before release.