feat(config,macos): add SnapshotMacOSPref and InferPreferenceType

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

Author: fullstackjam

internal/config/config.go

@@ -43,6 +43,7 @@ type Config struct {
 
 	SnapshotShell    *SnapshotShellConfig
 	SnapshotGit      *SnapshotGitConfig
+	SnapshotMacOS    []SnapshotMacOSPref
 	SnapshotDotfiles string
 	DotfilesURL      string
 	PostInstall      string
@@ -59,6 +60,13 @@ type SnapshotGitConfig struct {
 	UserEmail string
 }
 
+type SnapshotMacOSPref struct {
+	Domain string
+	Key    string
+	Value  string
+	Desc   string
+}
+
 type RemoteConfig struct {
 	Username     string   `json:"username"`
 	Slug         string   `json:"slug"`

internal/macos/macos.go

@@ -50,6 +50,36 @@ var DefaultPreferences = []Preference{
 	{"com.apple.TimeMachine", "DoNotOfferNewDisksForBackup", "bool", "true", "Don't prompt for Time Machine on new disks"},
 }
 
+func InferPreferenceType(value string) string {
+	switch strings.ToLower(value) {
+	case "true", "false", "1", "0", "yes", "no":
+		return "bool"
+	}
+	allDigits := true
+	for _, c := range value {
+		if c < '0' || c > '9' {
+			allDigits = false
+			break
+		}
+	}
+	if allDigits && value != "" {
+		return "int"
+	}
+	if strings.Contains(value, ".") {
+		allNumeric := true
+		for _, c := range strings.ReplaceAll(value, ".", "") {
+			if c < '0' || c > '9' {
+				allNumeric = false
+				break
+			}
+		}
+		if allNumeric {
+			return "float"
+		}
+	}
+	return "string"
+}
+
 func expandHome(path string) string {
 	if strings.HasPrefix(path, "~/") {
 		home, err := os.UserHomeDir()