Merge multi-module support from PR clockworklabs#3417 with upstream Uuid support

- Restored module_prefix field to UnrealCpp struct
- Added module_prefix parameter throughout codegen functions
- Preserved upstream's Uuid type support
- Fixed Result type codegen to pass module_prefix argument

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: Ludv1gL