refactor: 重构 token 管理，新增 NATS adapter 和多示例

按照 TOKEN_REFACTOR.md / FIX_CONFIG.md 方案重构核心层：
- miot: Init() 优先读 storage token，新增 RefreshAuthInfo() 和刷新回调
- xiaomi: Config 改用 AuthInfo 结构体（含 UUID/UID/DataDir/OnTokenRefreshed）
- xiaomi: NewClient(ctx, Config) 新签名，新增 RefreshToken()，后台自动刷新
- xiaomi/devices: 设备控制接口重构
- 新增示例 12_ac_subscribe，其余示例适配新 Config

xiaomi/client.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"sync"
+	"time"
 
 	"xiaomihome/miot"
 )
@@ -15,6 +16,7 @@ type Client struct {
 	http       *miot.MIoTHttpClient
 	mipsCloud  *miot.MipsCloudClient
 	specParser *miot.MIoTSpecParser
+	uuid       string
 	deviceMu   sync.RWMutex
 	devices    map[string]*miot.MIoTDevice
 
@@ -23,32 +25,48 @@ type Client struct {
 	mu        sync.RWMutex
 }
 
-// NewClient 创建并初始化客户端（零 miot import，一个 Config 搞定）。
+// NewClient 创建并初始化客户端。
 func NewClient(ctx context.Context, cfg Config) (*Client, error) {
+	if cfg.AuthInfo.AccessToken == "" {
+		return nil, fmt.Errorf("xiaomi: Config.AuthInfo.AccessToken is required")
+	}
+	if cfg.UUID == "" {
+		return nil, fmt.Errorf("xiaomi: Config.UUID is required")
+	}
+
+	if cfg.DataDir == "" {
+		cfg.DataDir = "./data"
+	}
+
+	// 计算 expires_ts（如果未提供，从 expires_in 推算）
+	expiresTS := float64(cfg.AuthInfo.ExpiresTS)
+	if expiresTS == 0 && cfg.AuthInfo.ExpiresIn > 0 {
+		expiresTS = float64(time.Now().Unix() + int64(cfg.AuthInfo.ExpiresIn))
+	}
+
+	uuid := cfg.UUID
 	entryData := map[string]interface{}{
-		"access_token": cfg.AccessToken,
+		"access_token":  cfg.AuthInfo.AccessToken,
+		"refresh_token": cfg.AuthInfo.RefreshToken,
+		"expires_ts":    expiresTS,
+		"uuid":          uuid,
 	}
 
 	miotClient := miot.NewMIoTClient("xiaomi_sdk", entryData, cfg.UID, "cn", miot.CtrlModeAuto)
-	miotClient.SetStorage(miot.NewMIoTStorage("./data"))
-	miotClient.SetSpecParser(miot.NewMIoTSpecParser("en", miot.NewMIoTStorage("./data"), "./data/specs"))
+	miotClient.SetStorage(miot.NewMIoTStorage(cfg.DataDir))
+	miotClient.SetSpecParser(miot.NewMIoTSpecParser("en", miot.NewMIoTStorage(cfg.DataDir), cfg.DataDir+"/specs"))
 
-	httpClient, err := miot.NewMIoTHttpClient("cn", miot.OAUTH2_CLIENT_ID, cfg.AccessToken)
+	httpClient, err := miot.NewMIoTHttpClient("cn", miot.OAUTH2_CLIENT_ID, cfg.AuthInfo.AccessToken)
 	if err != nil {
 		return nil, fmt.Errorf("xiaomi: http: %w", err)
 	}
 	miotClient.SetHTTPClient(httpClient)
 
-	// MIPS client ID 使用 config 中的 UUID，空则自动生成
-	mipsUUID := cfg.UUID
-	if mipsUUID == "" {
-		mipsUUID = generateUUID()
-	}
 	mipsCloud := miot.NewMipsCloudClient(
 		"ssl://cn-ha.mqtt.io.mi.com:8883",
-		"ha."+mipsUUID,
+		"ha."+uuid,
 		miot.OAUTH2_CLIENT_ID,
-		cfg.AccessToken,
+		cfg.AuthInfo.AccessToken,
 	)
 	miotClient.SetMipsCloud(mipsCloud)
 
@@ -56,20 +74,25 @@ func NewClient(ctx context.Context, cfg Config) (*Client, error) {
 		return nil, fmt.Errorf("xiaomi: init: %w", err)
 	}
 
-	// 初始刷新设备列表（对齐 full_client 示例）
 	_ = miotClient.RefreshDevices()
 
-	// 连接 MIPS（对齐 full_client 示例 line 83）
 	if err := mipsCloud.Connect(); err != nil {
 		return nil, fmt.Errorf("xiaomi: mips connect: %w", err)
 	}
 
+	// 启动后台 token 自动刷新
+	if cfg.OnTokenRefreshed != nil {
+		miotClient.SetTokenRefreshCallback(cfg.OnTokenRefreshed)
+	}
+	miotClient.RequestRefreshAuthInfo(10)
+
 	return &Client{
 		cfg:        cfg,
 		inner:      miotClient,
 		http:       httpClient,
 		mipsCloud:  mipsCloud,
-		specParser: miot.NewMIoTSpecParser("en", miot.NewMIoTStorage("./data"), "./data/specs"),
+		uuid:       uuid,
+		specParser: miot.NewMIoTSpecParser("en", miot.NewMIoTStorage(cfg.DataDir), cfg.DataDir+"/specs"),
 		devices:    make(map[string]*miot.MIoTDevice),
 		propSubs:  make(map[string]string),
 		eventSubs: make(map[string]string),
@@ -87,6 +110,21 @@ func (c *Client) Close() error {
 	return nil
 }
 
+// RefreshToken 手动刷新 token，返回新值供调用方持久化。
+func (c *Client) RefreshToken(ctx context.Context) (*TokenResult, error) {
+	result, err := c.inner.RefreshAuthInfo()
+	if err != nil {
+		return nil, fmt.Errorf("xiaomi: refresh token: %w", err)
+	}
+	return &TokenResult{
+		AccessToken:  strVal(result, "access_token"),
+		RefreshToken: strVal(result, "refresh_token"),
+		ExpiresIn:    intVal(result, "expires_in"),
+		ExpiresTS:    int64(intVal(result, "expires_ts")),
+		UID:          strVal(result, "uid"),
+	}, nil
+}
+
 func (c *Client) getOrCreateDevice(did string, info map[string]interface{}) *miot.MIoTDevice {
 	c.deviceMu.Lock()
 	defer c.deviceMu.Unlock()
@@ -94,7 +132,6 @@ func (c *Client) getOrCreateDevice(did string, info map[string]interface{}) *mio
 		return dev
 	}
 
-	// 从 device info 获取 URN 和 model 用于 SPEC 加载
 	urn, _ := info["urn"].(string)
 	model, _ := info["model"].(string)
 	var spec *miot.MIoTSpecInstance