first commit, i i have no idea what i have done

server/internal/models/device.go

@@ -0,0 +1,12 @@
+package models
+
+import "time"
+
+type Device struct {
+	GUID      string   `gorm:"primaryKey"`
+	Name      string   `gorm:"size:255;not null"`
+	Users     []User   `gorm:"many2many:user_devices;joinForeignKey:ID;joinReferences:GUID"`
+	Records   []Record `gorm:"foreignKey:DeviceGUID;references:GUID;constraint:OnDelete:CASCADE"`
+	CreatedAt time.Time
+	UpdatedAt time.Time
+}

server/internal/models/record.go

@@ -0,0 +1,13 @@
+package models
+
+import "time"
+
+type Record struct {
+	ID         uint   `gorm:"primaryKey"`
+	DeviceGUID string `gorm:"index;size:64;not null"`
+	StartedAt  int64  `gorm:"not null"`
+	StoppedAt  int64  `gorm:"not null"`
+	ObjectKey  string `gorm:"size:512;not null"`
+	CreatedAt  time.Time
+	UpdatedAt  time.Time
+}

server/internal/models/user.go

@@ -0,0 +1,20 @@
+package models
+
+import "time"
+
+type Role string
+
+const (
+	RoleAdmin Role = "admin"
+	RoleUser  Role = "user"
+)
+
+type User struct {
+	ID        uint     `gorm:"primaryKey"`
+	Username  string   `gorm:"uniqueIndex;size:255;not null"`
+	Password  string   `gorm:"not null"`
+	Role      Role     `gorm:"type:varchar(16);not null;default:'user'"`
+	Devices   []Device `gorm:"many2many:user_devices;joinForeignKey:ID;joinReferences:GUID"`
+	CreatedAt time.Time
+	UpdatedAt time.Time
+}