feat: 扩充 Docker 命令并新增 diagnose 状态诊断

- Docker：新增只读、生命周期、清理、Compose 共 32 条命令，Linux 自动适配 podman
- 危险命令 clearall/prunevolumes 未带 --yes 时仅提示并以退出码 2 结束
- 需要容器/镜像名的命令做必填参数校验，-- 之后参数计入位置参数
- diagnose：自动识别 Docker/Podman 容器或 K8s Pod，输出状态、根因、依据、建议并附日志与事件
- diagnose 中 -n 表示 namespace，其余命令 -n 仍为 --dry-run
- 新增内置动作桥接与平台变体 helper，补充单元/集成/CLI 测试与 README

internal/diagnose/options.go

@@ -0,0 +1,141 @@
+package diagnose
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Options controls what a diagnosis collects.
+type Options struct {
+	Kind      string // "", "docker" or "k8s"
+	Namespace string
+	Context   string
+	Lines     int
+	NoLogs    bool
+	NoEvents  bool
+	Container string
+}
+
+// DefaultLines is the number of log lines collected by default.
+const DefaultLines = 50
+
+// ParseArgs parses the arguments forwarded by the CLI. It returns the target
+// (container or Pod name) and the collection options.
+func ParseArgs(args []string) (string, Options, error) {
+	opts := Options{Lines: DefaultLines}
+	var targets []string
+	positionalOnly := false
+
+	for i := 0; i < len(args); i++ {
+		arg := args[i]
+		switch {
+		case positionalOnly:
+			targets = append(targets, arg)
+
+		case arg == "--":
+			positionalOnly = true
+
+		case arg == "--kind" || arg == "--kind=":
+			value, err := valueFor(arg, args, &i, "--kind")
+			if err != nil {
+				return "", opts, err
+			}
+			opts.Kind = strings.ToLower(value)
+			if opts.Kind != "docker" && opts.Kind != "k8s" {
+				return "", opts, fmt.Errorf("--kind 只支持 docker 或 k8s，收到 %q", value)
+			}
+
+		case strings.HasPrefix(arg, "--kind="):
+			opts.Kind = strings.ToLower(strings.TrimPrefix(arg, "--kind="))
+			if opts.Kind != "docker" && opts.Kind != "k8s" {
+				return "", opts, fmt.Errorf("--kind 只支持 docker 或 k8s，收到 %q", opts.Kind)
+			}
+
+		case arg == "--namespace" || arg == "-N":
+			value, err := valueFor(arg, args, &i, arg)
+			if err != nil {
+				return "", opts, err
+			}
+			opts.Namespace = value
+
+		case strings.HasPrefix(arg, "--namespace="):
+			opts.Namespace = strings.TrimPrefix(arg, "--namespace=")
+
+		case arg == "--context":
+			value, err := valueFor(arg, args, &i, arg)
+			if err != nil {
+				return "", opts, err
+			}
+			opts.Context = value
+
+		case strings.HasPrefix(arg, "--context="):
+			opts.Context = strings.TrimPrefix(arg, "--context=")
+
+		case arg == "--lines":
+			value, err := valueFor(arg, args, &i, arg)
+			if err != nil {
+				return "", opts, err
+			}
+			n, err := strconv.Atoi(value)
+			if err != nil || n <= 0 {
+				return "", opts, fmt.Errorf("--lines 需要正整数，收到 %q", value)
+			}
+			opts.Lines = n
+
+		case strings.HasPrefix(arg, "--lines="):
+			n, err := strconv.Atoi(strings.TrimPrefix(arg, "--lines="))
+			if err != nil || n <= 0 {
+				return "", opts, fmt.Errorf("--lines 需要正整数，收到 %q", strings.TrimPrefix(arg, "--lines="))
+			}
+			opts.Lines = n
+
+		case arg == "--no-logs":
+			opts.NoLogs = true
+
+		case arg == "--no-events":
+			opts.NoEvents = true
+
+		case arg == "--container" || arg == "-c":
+			value, err := valueFor(arg, args, &i, arg)
+			if err != nil {
+				return "", opts, err
+			}
+			opts.Container = value
+
+		case strings.HasPrefix(arg, "--container="):
+			opts.Container = strings.TrimPrefix(arg, "--container=")
+
+		case strings.HasPrefix(arg, "-") && arg != "-":
+			return "", opts, fmt.Errorf("未知选项 %q", arg)
+
+		default:
+			targets = append(targets, arg)
+		}
+	}
+
+	if len(targets) == 0 {
+		return "", opts, fmt.Errorf("必须提供容器名或 Pod 名，例如 kopsc diagnose web")
+	}
+	if len(targets) > 1 {
+		return "", opts, fmt.Errorf("一次只能诊断一个目标，收到 %d 个：%s", len(targets), strings.Join(targets, ", "))
+	}
+
+	if opts.Kind == "docker" && (opts.Namespace != "" || opts.Context != "") {
+		return "", opts, fmt.Errorf("Docker 诊断不支持 --namespace/--context；请改用 --kind k8s")
+	}
+
+	return targets[0], opts, nil
+}
+
+// valueFor reads the value of a flag written as "--flag value" or "--flag=".
+func valueFor(flag string, args []string, index *int, name string) (string, error) {
+	if strings.HasSuffix(flag, "=") {
+		return "", fmt.Errorf("%s 缺少参数", name)
+	}
+	if *index+1 >= len(args) {
+		return "", fmt.Errorf("%s 缺少参数，例如 %s value", name, name)
+	}
+	*index = *index + 1
+	return args[*index], nil
+}