test: Apply coderabbitai PR test feedback

Author: jentfoo

pkg/server/server_test.go

@@ -1,6 +1,7 @@
 package server
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/projectdiscovery/interactsh/pkg/settings"
@@ -19,7 +20,7 @@ func TestIsCorrelationID(t *testing.T) {
 	options := Options{CorrelationIdLength: settings.CorrelationIdLengthDefault, CorrelationIdNonceLength: settings.CorrelationIdNonceLengthDefault}
 
 	t.Run("exact length match", func(t *testing.T) {
-		id := xid.New().String() + "aaabbbbcccccc"
+		id := strings.Repeat("a", options.CorrelationIdLength) + strings.Repeat("b", options.CorrelationIdNonceLength)
 		require.True(t, options.isCorrelationID(id))
 	})
 
@@ -30,7 +31,7 @@ func TestIsCorrelationID(t *testing.T) {
 	t.Run("sliding window finds embedded ID", func(t *testing.T) {
 		shortNonce := Options{CorrelationIdLength: settings.CorrelationIdLengthDefault, CorrelationIdNonceLength: 4}
 		validID := xid.New().String() + "abcd"
-		longer := validID + "extrapaddi" // simulates client with longer nonce
+		longer := ".." + validID + ".." // non-alphanumeric padding prevents spurious matches
 		found := false
 		for chunk := range stringsutil.SlideWithLength(longer, shortNonce.GetIdLength()) {
 			if shortNonce.isCorrelationID(chunk) {