wip(py): initial python bindings

[XAMPPRocky]

The goal of this PR is provide a package and Pythonic API to rasn for working with ASN.1 in Python. The goal for the initial bindings is get to following example to fully compile and work, alongside all of the infrastructure needed to release and ship python packages.

@rasn.sequence
class UserRecord:
    id: rasn.types.Integer
    oid: rasn.types.ObjectIdentifier
    age: rasn.types.Integer
    department: Department

@rasn.sequence(tag=(Tag.EXPLICIT, 1))
class Department:
  name: rasn.types.OctetString
  code: rasn.types.Integer

user = UserRecord(id=123, data=b"test", age=30)
encoded = user.encode(rasn.Codec.DER)

print(base64.b64encode(encoded))
print(UserRecord.decode(encoded))

[Nicceboy]

Some "competition" coming up, Trail of Bits trying to bring DER Python bindings for Rust-based projects: https://blog.trailofbits.com/2025/04/18/sneak-peek-a-new-asn.1-api-for-python/