purego requires dynamic linking, so split the agent builds:
- Default: static binary without NVML (works on musl/alpine)
- Glibc: dynamic binary with NVML support via purego
Changes:
- Add glibc build tag to conditionally include NVML code
- Add beszel-agent-linux-amd64-glibc build/archive in goreleaser
- Update ghupdate to use glibc binary on glibc systems
- Switch nvidia dockerfile to golang:bookworm with -tags glibc
