feat: add device hotplug event notifications (USB on Linux)

pkg/devices/events/events.go

@@ -0,0 +1,57 @@
+package events
+
+import "context"
+
+type EventSource interface {
+	Kind() Kind
+	Start(ctx context.Context) (<-chan *DeviceEvent, error)
+	Stop() error
+}
+
+type Action string
+
+const (
+	ActionAdd    Action = "add"
+	ActionRemove Action = "remove"
+	ActionChange Action = "change"
+)
+
+type Kind string
+
+const (
+	KindUSB       Kind = "usb"
+	KindBluetooth Kind = "bluetooth"
+	KindPCI       Kind = "pci"
+	KindGeneric   Kind = "generic"
+)
+
+type DeviceEvent struct {
+	Action       Action
+	Kind         Kind
+	DeviceID     string            // e.g. "1-2" for USB bus 1 dev 2
+	Vendor       string            // Vendor name or ID
+	Product      string            // Product name or ID
+	Serial       string            // Serial number if available
+	Capabilities string            // Human-readable capability description
+	Raw          map[string]string // Raw properties for extensibility
+}
+
+func (e *DeviceEvent) FormatMessage() string {
+	actionEmoji := "🔌"
+	actionText := "Connected"
+	if e.Action == ActionRemove {
+		actionEmoji = "🔌"
+		actionText = "Disconnected"
+	}
+
+	msg := actionEmoji + " Device " + actionText + "\n\n"
+	msg += "Type: " + string(e.Kind) + "\n"
+	msg += "Device: " + e.Vendor + " " + e.Product + "\n"
+	if e.Capabilities != "" {
+		msg += "Capabilities: " + e.Capabilities + "\n"
+	}
+	if e.Serial != "" {
+		msg += "Serial: " + e.Serial + "\n"
+	}
+	return msg
+}