VM start, image build, and network/setup failures were hard to diagnose because bangerd emitted almost no lifecycle logs and the Firecracker SDK logger was discarded. This adds a daemon-wide JSON logger with configurable log level so failures leave breadcrumbs instead of only side effects.
Log the main daemon and VM lifecycle stages, preserve raw Firecracker and image-build helper output in dedicated files, and include those log paths in daemon status and returned errors. Bridge SDK logrus output into the daemon logger at debug level so low-level Firecracker diagnostics are available without making normal info logs unreadable.
Validation: go test ./... and make build. Left unrelated worktree changes out of this commit, including internal/api/types.go, the deleted shell scripts, and my-rootfs.ext4.
Replace the daemon's hand-rolled Firecracker process/socket client with the official firecracker-go-sdk while keeping the existing VM lifecycle and host-side disk and TAP setup intact.
Build machine configs through the SDK, launch Firecracker through a sudo process runner, resolve the real VM PID after startup, and use the SDK client for Ctrl-Alt-Del instead of raw REST calls. Drop the unused cached Firecracker state and add focused adapter tests for config and process-runner wiring.
Validated with go mod tidy, go test ./..., and make build. A live KVM/Firecracker smoke boot was not run in this environment.
Replace the shell-only user workflow with `banger` and `bangerd`: Cobra commands, XDG/SQLite-backed state, managed VM and image lifecycle, and a Bubble Tea TUI for browsing and operating VMs.\n\nKeep Firecracker orchestration behind the daemon so VM specs become persistent objects, and add repo entrypoints for building, installing, and documenting the new flow while still delegating rootfs customization to the existing shell tooling.\n\nHarden the control plane around real usage by reclaiming Firecracker API sockets for the user, restarting stale daemons after rebuilds, and returning the correct `vm.create` payload so the CLI and TUI creation flow work reliably.\n\nValidation: `go test ./...`, `make build`, and a host-side smoke test with `./banger vm create --name codex-smoke`.
