init monlet repo with stage 0-2 (docs, contract, agent MVP)

agent/internal/client/backoff.go

@@ -0,0 +1,29 @@
+package client
+
+import (
+	"math/rand/v2"
+	"time"
+)
+
+const (
+	BackoffMin = 1 * time.Second
+	BackoffMax = 30 * time.Second
+)
+
+// Delay computes exponential backoff with ±20% jitter.
+// attempt starts at 1 for the first failed try.
+func Delay(attempt int) time.Duration {
+	if attempt < 1 {
+		attempt = 1
+	}
+	d := BackoffMin
+	for i := 1; i < attempt; i++ {
+		d *= 2
+		if d >= BackoffMax {
+			d = BackoffMax
+			break
+		}
+	}
+	jitter := 1.0 + (rand.Float64()*0.4 - 0.2)
+	return time.Duration(float64(d) * jitter)
+}