feat: add Timeweb Cloud provider for Woodpecker CI autoscaler

- Implement timewebcloud provider with DeployAgent, RemoveAgent, ListDeployedAgentNames
- Add minimal HTTP API client for Timeweb Cloud (create/list/delete servers)
- Register provider in main.go with CLI flags
- Add timeweb-list and timeweb-tester utilities
- Include Dockerfile and docker-compose.yml for deployment
- Update DEPLOY.md with verified OS/preset IDs

utils/random.go

@@ -0,0 +1,18 @@
+package utils
+
+import (
+	"math/rand"
+	"time"
+)
+
+// RandomString generates a random string of length n using alphanumeric characters.
+func RandomString(n int) string {
+	letterRunes := []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
+	rng := rand.New(rand.NewSource(time.Now().UnixNano()))
+
+	b := make([]rune, n)
+	for i := range b {
+		b[i] = letterRunes[rng.Intn(len(letterRunes))]
+	}
+	return string(b)
+}