feat(bridge): MQTT bridge with Home Assistant auto-discovery

pkg/bridge/utils.go

@@ -0,0 +1,22 @@
+package bridge
+
+import (
+	"fmt"
+	"strings"
+)
+
+func inputLabel(in int) string { return fmt.Sprintf("IN%d", in) }
+
+func inputNumberFromLabel(label string) int {
+	label = strings.ToUpper(strings.TrimSpace(label))
+	for i := 1; i <= numInputs; i++ {
+		if label == inputLabel(i) {
+			return i
+		}
+	}
+	var n int
+	if _, err := fmt.Sscanf(label, "%d", &n); err == nil && n >= 1 && n <= numInputs {
+		return n
+	}
+	return 0
+}