v0.3.1-rc0

What's Changed

• Update use of environment variable in ps.py by @HubertZhang in #73
• misc: split ps.py file into multiple files by @specture724 in #64
• feat: cache device uuid in VllmWorkerExtension by @kip-cxj in #74

Full Changelog: v0.3.0-rc1...v0.3.1-rc0