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_test.go

@@ -0,0 +1,42 @@
+package utils_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.woodpecker-ci.org/autoscaler/utils"
+)
+
+func TestRandomString(t *testing.T) {
+	tests := []struct {
+		name string
+		n    int
+		want int
+	}{
+		{
+			name: "zero length",
+			n:    0,
+			want: 0,
+		},
+		{
+			name: "length 10",
+			n:    10,
+			want: 10,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			str := utils.RandomString(tt.n)
+			assert.Equal(t, tt.want, len(str))
+		})
+
+		t.Run("alphanumeric", func(t *testing.T) {
+			str1 := utils.RandomString(10)
+			for _, r := range str1 {
+				assert.Contains(t, "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ", string(r))
+			}
+		})
+	}
+}