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/devices/thermostat.go

@@ -0,0 +1,140 @@
+package devices
+
+import (
+	"context"
+	"xiaomihome/xiaomi"
+)
+
+// Thermostat 温控器/电热毯统一控制接口
+type Thermostat interface {
+	Device
+	TurnOn(ctx context.Context) error
+	TurnOff(ctx context.Context) error
+	IsOn(ctx context.Context) (bool, error)
+
+	SetTargetTemp(ctx context.Context, celsius float64) error
+	GetTargetTemp(ctx context.Context) (float64, error)
+
+	GetCurrentTemp(ctx context.Context) (float64, error)
+
+	SetHeating(ctx context.Context, on bool) error
+	IsHeating(ctx context.Context) (bool, error)
+}
+
+type thermostatDevice struct {
+	BaseDevice
+	propOn          siidPiid // "on"
+	propTargetTemp  siidPiid // "target-temperature"
+	propCurrentTemp siidPiid // "temperature"
+	propHeating     siidPiid // "heating" or "mode"
+}
+
+// NewThermostat creates a Thermostat control for the given device.
+func NewThermostat(client *xiaomi.Client, info *xiaomi.DeviceInfo) (Thermostat, error) {
+	d := &thermostatDevice{
+		BaseDevice: NewBaseDevice(client, info),
+	}
+
+	resolver := d.getSpecResolver()
+	if resolver == nil {
+		return nil, xiaomi.ErrNoSPEC
+	}
+
+	siid, piid, ok := resolver.find("on")
+	if !ok {
+		return nil, xiaomi.ErrNotSupported
+	}
+	d.propOn = siidPiid{siid, piid, true}
+
+	if s, p, ok := resolver.find("target-temperature"); ok {
+		d.propTargetTemp = siidPiid{s, p, true}
+	}
+	if s, p, ok := resolver.find("temperature"); ok {
+		d.propCurrentTemp = siidPiid{s, p, true}
+	}
+	if s, p, ok := resolver.find("heating"); ok {
+		d.propHeating = siidPiid{s, p, true}
+	} else if s, p, ok := resolver.find("heater"); ok {
+		d.propHeating = siidPiid{s, p, true}
+	}
+
+	return d, nil
+}
+
+func (d *thermostatDevice) TurnOn(ctx context.Context) error {
+	if !d.propOn.valid {
+		return xiaomi.ErrNotSupported
+	}
+	return d.SetProp(ctx, d.propOn.siid, d.propOn.piid, true)
+}
+
+func (d *thermostatDevice) TurnOff(ctx context.Context) error {
+	if !d.propOn.valid {
+		return xiaomi.ErrNotSupported
+	}
+	return d.SetProp(ctx, d.propOn.siid, d.propOn.piid, false)
+}
+
+func (d *thermostatDevice) IsOn(ctx context.Context) (bool, error) {
+	if !d.propOn.valid {
+		return false, xiaomi.ErrNotSupported
+	}
+	prop, err := d.GetProp(ctx, d.propOn.siid, d.propOn.piid)
+	if err != nil {
+		return false, err
+	}
+	if b, ok := prop.Value.(bool); ok {
+		return b, nil
+	}
+	return false, nil
+}
+
+func (d *thermostatDevice) SetTargetTemp(ctx context.Context, celsius float64) error {
+	if !d.propTargetTemp.valid {
+		return xiaomi.ErrNotSupported
+	}
+	return d.SetProp(ctx, d.propTargetTemp.siid, d.propTargetTemp.piid, celsius)
+}
+
+func (d *thermostatDevice) GetTargetTemp(ctx context.Context) (float64, error) {
+	if !d.propTargetTemp.valid {
+		return 0, xiaomi.ErrNotSupported
+	}
+	prop, err := d.GetProp(ctx, d.propTargetTemp.siid, d.propTargetTemp.piid)
+	if err != nil {
+		return 0, err
+	}
+	return toFloat(prop.Value), nil
+}
+
+func (d *thermostatDevice) GetCurrentTemp(ctx context.Context) (float64, error) {
+	if !d.propCurrentTemp.valid {
+		return 0, xiaomi.ErrNotSupported
+	}
+	prop, err := d.GetProp(ctx, d.propCurrentTemp.siid, d.propCurrentTemp.piid)
+	if err != nil {
+		return 0, err
+	}
+	return toFloat(prop.Value), nil
+}
+
+func (d *thermostatDevice) SetHeating(ctx context.Context, on bool) error {
+	if !d.propHeating.valid {
+		return xiaomi.ErrNotSupported
+	}
+	return d.SetProp(ctx, d.propHeating.siid, d.propHeating.piid, on)
+}
+
+func (d *thermostatDevice) IsHeating(ctx context.Context) (bool, error) {
+	if !d.propHeating.valid {
+		return false, xiaomi.ErrNotSupported
+	}
+	prop, err := d.GetProp(ctx, d.propHeating.siid, d.propHeating.piid)
+	if err != nil {
+		return false, err
+	}
+	if b, ok := prop.Value.(bool); ok {
+		return b, nil
+	}
+	return false, nil
+}