feat: 添加设备IMEI和单卡ICCID查询接口

- 新增 GET /api/admin/devices/by-imei/:imei 接口，支持通过设备号查询设备详情
- 新增 GET /api/admin/iot-cards/by-iccid/:iccid 接口，支持通过ICCID查询单卡详情
- 添加对应的 Service 层方法和 Handler
- 更新 OpenAPI 文档
- 添加集成测试并修复测试环境配置（使用环境变量）
- 归档已完成的 OpenSpec 变更记录

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

internal/routes/device.go

@@ -28,6 +28,14 @@ func registerDeviceRoutes(router fiber.Router, handler *admin.DeviceHandler, imp
 		Auth:    true,
 	})
 
+	Register(devices, doc, groupPath, "GET", "/by-imei/:imei", handler.GetByIMEI, RouteSpec{
+		Summary: "通过设备号查询设备详情",
+		Tags:    []string{"设备管理"},
+		Input:   new(dto.GetDeviceByIMEIRequest),
+		Output:  new(dto.DeviceResponse),
+		Auth:    true,
+	})
+
 	Register(devices, doc, groupPath, "DELETE", "/:id", handler.Delete, RouteSpec{
 		Summary:     "删除设备",
 		Description: "仅平台用户可操作。删除设备时自动解绑所有卡（卡不会被删除）。",

internal/routes/iot_card.go

@@ -20,6 +20,14 @@ func registerIotCardRoutes(router fiber.Router, handler *admin.IotCardHandler, i
 		Auth:    true,
 	})
 
+	Register(iotCards, doc, groupPath, "GET", "/by-iccid/:iccid", handler.GetByICCID, RouteSpec{
+		Summary: "通过ICCID查询单卡详情",
+		Tags:    []string{"IoT卡管理"},
+		Input:   new(dto.GetIotCardByICCIDRequest),
+		Output:  new(dto.IotCardDetailResponse),
+		Auth:    true,
+	})
+
 	Register(iotCards, doc, groupPath, "POST", "/import", importHandler.Import, RouteSpec{
 		Summary: "批量导入IoT卡（ICCID+MSISDN）",
 		Description: `## ⚠️ 接口变更说明（BREAKING CHANGE）