Remind users when a VM is still running after hanger vm ssh exits instead of silently dropping them back to the host shell.\n\nAttach a Firecracker vsock device to each VM, persist the host vsock path/CID,\nadd a new guest-side banger-vsock-pingd responder to the runtime bundle and both\nimage-build paths, and expose a vm.ping RPC that the CLI and TUI call after SSH\nreturns. Doctor and start/build preflight now validate the helper plus\n/dev/vhost-vsock so the feature fails early and clearly.\n\nValidated with go mod tidy, bash -n customize.sh, git diff --check, make build,\nand GOCACHE=/tmp/banger-gocache go test ./... outside the sandbox because the\ndaemon tests need real Unix/UDP sockets. Rebuild the image/rootfs used for new\nVMs so the guest ping service is present.
Make host-integrated VM features fit a standard Go extension path instead of adding more one-off branches through vm.go. This is the enabling refactor for future work like shared mounts, not the /work feature itself.
Add a daemon capability pipeline plus a structured guest-config builder, then move the existing /root work-disk mount, built-in DNS, and NAT wiring onto those hooks. Generalize Firecracker drive config at the same time so later storage features can extend machine setup without another hardcoded path.
Add banger doctor on top of the shared readiness checks, update the docs to describe the new architecture, and cover the new seams with guest-config, capability, report, CLI, and full go test verification. Also verify make build and a real ./banger doctor run on the host.
