[Feature] Possibly remove libcargo dependency?

[oxalica]

cargo library is heavy and hard to compile (#50 #51). I don't think the main functionality, disassembling, has anything to do with openssl and libgit dependencies.

Since we are a cargo subcommand, the cargo binary is almost always available through CARGO env var (which may be from package manager) . Could we just using the CLI interface of cargo without pulling the library, or is there anything can only work with libcargo?