feat: default state-dir to /var/lib/cocoon-macos (mirror cocoon's /var/lib/cocoon)

Was ~/.cocoon-macos; now /var/lib/cocoon-macos so a system-installed binary (/usr/bin/cocoon-macos,
run as root for KVM/netns/qemu-nbd) keeps VM state, the cloudimg store and shared firmware in the
canonical system location, parallel to cocoon. --state-dir and $COCOON_MACOS_HOME still override.

Author: CMGS

README.md

@@ -38,7 +38,7 @@ disk image to ghcr; a thin Go CLI clones that image and boots VMs from it.
 ```bash
 go build -o cocoon-macos .
 
-# pull the golden qcow2 from ghcr into the local store (cocoon cloudimg; ~/.cocoon-macos)
+# pull the golden qcow2 from ghcr into the local store (cocoon cloudimg; /var/lib/cocoon-macos)
 cocoon-macos image pull ghcr.io/cocoonstack/cocoon-macos/tahoe:26
 cocoon-macos image list        # also: inspect, rm
 
@@ -72,7 +72,7 @@ cocoon-macos vm clone    m1 -n m2 --ssh-port 2223 --random-smbios
 `vm run` does: `qemu-img create -b <golden> overlay.qcow2` (instant CoW clone) → copy a
 per-VM `OVMF_VARS` → launch `qemu-system-x86_64` (validated OSX-KVM recipe in `qemu/launch.go`:
 Skylake-Client CPU spoofing GenuineIntel + `isa-applesmc` OSK + OVMF + OpenCore + the macOS
-qcow2) daemonized, recording state under `$COCOON_MACOS_HOME` (default `~/.cocoon-macos`).
+qcow2) daemonized, recording state under `--state-dir` / `$COCOON_MACOS_HOME` (default `/var/lib/cocoon-macos`, mirroring cocoon's `/var/lib/cocoon`).
 
 With `--random-smbios`, `create` also copies OpenCore per-VM and injects a generated identity
 into its `config.plist` `PlatformInfo/Generic` (via `qemu-nbd` mount); the model stays `iMac19,1`

cmd/firmware/commands.go

@@ -12,7 +12,7 @@ type Actions interface {
 // Command builds the `firmware` subcommand tree.
 func Command(h Actions) *cobra.Command {
 	fwCmd := &cobra.Command{Use: "firmware", Short: "Manage shared OpenCore/OVMF firmware under <state-dir>/firmware"}
-	fwCmd.PersistentFlags().String("state-dir", "", "VM state root (default $COCOON_MACOS_HOME or ~/.cocoon-macos)")
+	fwCmd.PersistentFlags().String("state-dir", "", "VM state root (default $COCOON_MACOS_HOME or /var/lib/cocoon-macos)")
 
 	installCmd := &cobra.Command{
 		Use:   "install",

cmd/firmware/handler.go

@@ -31,8 +31,7 @@ func stateDir(cmd *cobra.Command) string {
 	if d := os.Getenv("COCOON_MACOS_HOME"); d != "" {
 		return d
 	}
-	home, _ := os.UserHomeDir()
-	return filepath.Join(home, ".cocoon-macos")
+	return "/var/lib/cocoon-macos" // mirrors cocoon's /var/lib/cocoon
 }
 
 func dir(cmd *cobra.Command) string { return filepath.Join(stateDir(cmd), "firmware") }

cmd/image/commands.go

@@ -13,7 +13,7 @@ type Actions interface {
 // Command builds the `image` subcommand tree against the given handler.
 func Command(h Actions) *cobra.Command {
 	imageCmd := &cobra.Command{Use: "image", Short: "Manage macOS disk images (reuses cocoon's cloudimg store)"}
-	imageCmd.PersistentFlags().String("state-dir", "", "image/VM state root (default $COCOON_MACOS_HOME or ~/.cocoon-macos)")
+	imageCmd.PersistentFlags().String("state-dir", "", "image/VM state root (default $COCOON_MACOS_HOME or /var/lib/cocoon-macos)")
 
 	pull := &cobra.Command{
 		Use:   "pull REF",

cmd/image/handler.go

@@ -30,8 +30,7 @@ func stateDir(cmd *cobra.Command) string {
 	if d := os.Getenv("COCOON_MACOS_HOME"); d != "" {
 		return d
 	}
-	home, _ := os.UserHomeDir()
-	return filepath.Join(home, ".cocoon-macos")
+	return "/var/lib/cocoon-macos" // mirrors cocoon's /var/lib/cocoon
 }
 
 func (h *Handler) store(cmd *cobra.Command) (context.Context, *cloudimg.CloudImg, error) {

cmd/vm/commands.go

@@ -24,7 +24,7 @@ type Actions interface {
 func Command(h Actions) *cobra.Command {
 	vmCmd := &cobra.Command{Use: "vm", Short: "Manage macOS VMs"}
 	// state-dir applies to every subcommand (locating VM records), so make it persistent
-	vmCmd.PersistentFlags().String("state-dir", "", "VM state root (default $COCOON_MACOS_HOME or ~/.cocoon-macos)")
+	vmCmd.PersistentFlags().String("state-dir", "", "VM state root (default $COCOON_MACOS_HOME or /var/lib/cocoon-macos)")
 
 	createCmd := &cobra.Command{
 		Use:   "create [flags] IMAGE",

cmd/vm/handler.go

@@ -26,6 +26,7 @@ import (
 const (
 	qemuBinary      = "qemu-system-x86_64"
 	stopGracePeriod = 10 * time.Second
+	defaultStateDir = "/var/lib/cocoon-macos" // mirrors cocoon's /var/lib/cocoon; override via --state-dir or $COCOON_MACOS_HOME
 )
 
 // resolveBase returns the immutable base qcow2 for IMAGE: a direct filesystem path (legacy), else
@@ -134,8 +135,7 @@ func stateDir(cmd *cobra.Command) string {
 	if d := os.Getenv("COCOON_MACOS_HOME"); d != "" {
 		return d
 	}
-	home, _ := os.UserHomeDir()
-	return filepath.Join(home, ".cocoon-macos")
+	return defaultStateDir // /var/lib/cocoon-macos, mirroring cocoon's /var/lib/cocoon
 }
 
 func vmDir(cmd *cobra.Command, name string) string {