feat(packets): prevent duplicit usings inside source generator

Merge pull request #47 from Rutherther/feat/pass-nullable

Pass CanBeNull to string serializer and converter

feat(packets): pass nullable to packet serializers

fix(packets): make generator work with packets that have 0 members

feat: split packets definitions into separate assembly

Merge pull request #14 from Rutherther/packets-span

Rewrite packets string enumerator to use spans, add Injector for .NET 5+

feat: use ReadOnlySpan for deserialization instead of strings

refactor: split string converters

Merge pull request #16 from Rutherther/packets-list-inline-serializer

Add generation of packet list inline serializer

feat: add inline list converter

feat: split inline generated deserialization into different methods

Merge pull request #12 from Rutherther/packets

Implement custom packet serializer

fix: check for null after popping the string enumerator level

fix: return correct result type in converter generator when skipping

feat: add support for conditional packet attribute

feat: add checking parameter method for the generator

feat: rewrite packet serializer generator