wit: empty namespaces #1329

What happened?

When a WIT interface name has no package namespace (e.g. a plain "exports" interface rather than wasi:http/types), the code generator produces invalid Rust paths with a leading :: separator:

// Generated (broken):
impl<I: ...> ::Types<...> for ...

// Should be:
impl<I: ...> Types<...> for ...

Steps to Reproduce

Use a WIT world with unqualified interface names (no package prefix):

world root {
  import wasi:filesystem/types@0.2.0;
  export executor;  // no package namespace
}

Expected Results

Generates valid Rust: impl<I: ...> Types<...> for ...

Actual Results

TODO: What actually happened?

Versions and Environment

Hyperlight version or commit: TODO

OS Version

Run the following to find your OS version:

Linux:

cat /etc/os-release && uname -a

Windows (PowerShell):

cmd /c ver

Hypervisor

Run the following to check hypervisor access:

Linux:

ls -la /dev/kvm /dev/mshv 2>&1; getfacl /dev/kvm /dev/mshv 2>&1; id
[ -r /dev/kvm ] && [ -w /dev/kvm ] && echo "KVM: OK" || echo "KVM: FAIL"
[ -r /dev/mshv ] && [ -w /dev/mshv ] && echo "MSHV: OK" || echo "MSHV: FAIL"

Windows (Admin PowerShell):

Get-WindowsOptionalFeature -Online | Where-Object {$_.FeatureName -match 'Hyper-V|HypervisorPlatform|VirtualMachinePlatform'} | Format-Table

Extra Info

Anything else you'd like to add?