test(storage): 使用进程内 DNS 夹具消除离线测试依赖 (#689)

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

backend/internal/app/admin_channel_test.go

@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"infinite-canvas/backend/internal/model"
+	"infinite-canvas/backend/internal/outbound/outboundtest"
 	"infinite-canvas/backend/internal/repository"
 
 	"gorm.io/driver/sqlite"
@@ -470,6 +471,7 @@ func TestNormalizeAdminChannelModelDeleteIDsRequiresBoundedSelection(t *testing.
 }
 
 func TestResolveProviderConfigMapsSKUToProviderModel(t *testing.T) {
+	outboundtest.PublicDNS(t, "ark.cn-beijing.volces.com")
 	svc, db := newChannelModelTestService(t)
 	svc.dataDir = t.TempDir()
 	channel := model.ModelChannel{

backend/internal/app/resource_test.go

@@ -20,6 +20,7 @@ import (
 
 	"infinite-canvas/backend/internal/assets"
 	"infinite-canvas/backend/internal/model"
+	"infinite-canvas/backend/internal/outbound/outboundtest"
 	"infinite-canvas/backend/internal/repository"
 	"infinite-canvas/backend/internal/storage"
 
@@ -335,6 +336,7 @@ func TestAliyunOSSSettingKeepsCDNBaseURL(t *testing.T) {
 }
 
 func TestQiniuKodoSettingAllowsMissingCDNBaseURL(t *testing.T) {
+	outboundtest.PublicDNS(t, "up-z0.qiniup.com")
 	next, err := ossSettingFromRequest(OSSSettingRequest{
 		Enabled: true, Provider: qiniuKodoProvider, Region: "z0", Endpoint: "https://up-z0.qiniup.com",
 		Bucket: "private-bucket", AccessKeyID: "access-id", AccessKeySecret: "secret-value",
@@ -415,6 +417,7 @@ func TestArchivedProviderCredentialsAreEncryptedAtRest(t *testing.T) {
 }
 
 func TestResourceAccessChecksOwnershipAndSignsOSSResource(t *testing.T) {
+	outboundtest.PublicDNS(t, "s3.amazonaws.com")
 	svc := newResourceTestService(t)
 	settingJSON, _ := json.Marshal(ossSettingValue{
 		Enabled: true, Provider: "aliyun", Endpoint: "https://s3.amazonaws.com", Bucket: "private-bucket",
@@ -472,6 +475,7 @@ func TestPrepareResourceDeliveryPrefersConfiguredCDN(t *testing.T) {
 }
 
 func TestPrepareResourceDeliveryFallsBackToOriginWhenCDNAuthIsMissing(t *testing.T) {
+	outboundtest.PublicDNS(t, "s3.amazonaws.com")
 	svc := newResourceTestService(t)
 	settingJSON, _ := json.Marshal(ossSettingValue{
 		Enabled: true, Provider: aliyunOSSProvider, Endpoint: "https://s3.amazonaws.com", CDNBaseURL: "https://media.example.com",
@@ -687,6 +691,7 @@ func TestHistoricalUserResourceWithoutStorageSettingIDKeepsItsProviderCDN(t *tes
 }
 
 func TestPrepareResourceDeliveryUsesSignedOriginWithoutCDN(t *testing.T) {
+	outboundtest.PublicDNS(t, "s3.amazonaws.com")
 	svc := newResourceTestService(t)
 	settingJSON, _ := json.Marshal(ossSettingValue{
 		Enabled: true, Provider: aliyunOSSProvider, Endpoint: "https://s3.amazonaws.com", Bucket: "private-bucket",