chore: 提交高层 xiaomi 封装库及示例

- 新增 xiaomi/examples/ 下 8 个示例程序（用户/家庭查询、设备列表、开关/灯光/空调控制、属性订阅、高级过滤分类、SPEC 解析）
- miot_client_sub.go: 重构 SubProp/SubEvent，使用 buildPropTopic/buildEventTopic 支持通配符订阅（siid/piid=0 → +），并修复锁顺序问题（将 RequestRefreshProp 移到 Lock 外）
- spec_parser.go: 新增 downloadSpecFile 方法，本地 SPEC 文件缺失时自动从 miot-spec.org 下载
- ARCH_PLAN.md: 架构设计从 Proposed 更新为 Accepted（v1.0→v1.1），补充设备分类/工厂/SPEC 映射等模块设计
- xiaomi/: 新增 miot 上层强类型封装模块，包含 Client 主入口、用户/家庭/设备 API、属性读写、动作调用、订阅通知，以及 devices/ 设备控制抽象（Switch/Light/AirConditioner/Fan/Cover/Humidifier/Vacuum/WaterHeater/Thermostat）和 specs/ SPEC 查询辅助
- 更多 xiaomi 示例（风扇/窗帘/传感器控制）

xiaomi/examples/07_prop_subscribe/data/cert/mihome_ca.cert

@@ -0,0 +1,21 @@
+-----BEGIN CERTIFICATE-----
+MIIBazCCAQ+gAwIBAgIEA/UKYDAMBggqhkjOPQQDAgUAMCIxEzARBgNVBAoTCk1p
+amlhIFJvb3QxCzAJBgNVBAYTAkNOMCAXDTE2MTEyMzAxMzk0NVoYDzIwNjYxMTEx
+MDEzOTQ1WjAiMRMwEQYDVQQKEwpNaWppYSBSb290MQswCQYDVQQGEwJDTjBZMBMG
+ByqGSM49AgEGCCqGSM49AwEHA0IABL71iwLa4//4VBqgRI+6xE23xpovqPCxtv96
+2VHbZij61/Ag6jmi7oZ/3Xg/3C+whglcwoUEE6KALGJ9vccV9PmjLzAtMAwGA1Ud
+EwQFMAMBAf8wHQYDVR0OBBYEFJa3onw5sblmM6n40QmyAGDI5sURMAwGCCqGSM49
+BAMCBQADSAAwRQIgchciK9h6tZmfrP8Ka6KziQ4Lv3hKfrHtAZXMHPda4IYCIQCG
+az93ggFcbrG9u2wixjx1HKW4DUA5NXZG0wWQTpJTbQ==
+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

xiaomi/examples/07_prop_subscribe/main.go

@@ -0,0 +1,72 @@
+// Package main demonstrates property and device state subscriptions for all devices.
+// Press Ctrl+C to exit.
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+	"os/signal"
+
+	miotconfig "xiaomihome/miot/examples/config"
+	"xiaomihome/xiaomi"
+)
+
+func main() {
+	ctx := context.Background()
+
+	cfg, err := miotconfig.LoadConfig("../../../miot/examples/config.json")
+	if err != nil {
+		log.Fatal("请先运行 miot/examples/cloud_oauth 获取 token:", err)
+	}
+
+	client, err := xiaomi.NewClient(ctx, xiaomi.Config{
+		ClientSecret: "",
+		AccessToken:  cfg.AuthInfo.AccessToken,
+		UID:          cfg.UID,
+		UUID:         cfg.UUID,
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer client.Close()
+
+	devList, err := client.GetDevices(ctx, xiaomi.FilterByOnline())
+	if err != nil {
+		log.Fatal("获取设备列表失败:", err)
+	}
+	if len(devList) == 0 {
+		log.Fatal("未找到任何在线设备")
+	}
+
+	log.Printf("找到 %d 个在线设备，开始订阅...", len(devList))
+
+	for _, dev := range devList {
+		did := dev.DID
+		name := dev.Name
+
+		// 订阅该设备所有属性
+		subID, err := client.SubProp(did, 0, 0,
+			func(did string, p *xiaomi.PropertyValue) {
+				log.Printf("[%s] siid=%d piid=%d value=%v", name, p.SIID, p.PIID, p.Value)
+			})
+		if err != nil {
+			log.Printf("[%s] 订阅失败: %v", name, err)
+		} else {
+			log.Printf("[%s] 已订阅 subID=%s", name, subID)
+		}
+
+		// 订阅设备在线状态
+		if err := client.SubDeviceState(did, func(did string, state xiaomi.DeviceState) {
+			log.Printf("[%s] 状态变化: %s", name, state)
+		}); err != nil {
+			log.Printf("[%s] 状态订阅失败: %v", name, err)
+		}
+	}
+
+	log.Println("\n按 Ctrl+C 退出...")
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, os.Interrupt)
+	<-sigCh
+	log.Println("已退出")
+}