Fix async FakeIP save

transport/fakeip/memory.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing/common/cache"
+	"github.com/sagernet/sing/common/logger"
 )
 
 var _ adapter.FakeIPStorage = (*MemoryStorage)(nil)
@@ -34,6 +35,10 @@ func (s *MemoryStorage) FakeIPStore(address netip.Addr, domain string) error {
 	return nil
 }
 
+func (s *MemoryStorage) FakeIPStoreAsync(address netip.Addr, domain string, logger logger.Logger) {
+	s.domainCache.Store(address, domain)
+}
+
 func (s *MemoryStorage) FakeIPLoad(address netip.Addr) (string, bool) {
 	return s.domainCache.Load(address)
 }

transport/fakeip/store.go

@@ -95,12 +95,7 @@ func (s *Store) Create(domain string, strategy dns.DomainStrategy) (netip.Addr,
 		s.inet6Current = nextAddress
 		address = nextAddress
 	}
-	go func() {
-		err := s.storage.FakeIPStore(address, domain)
-		if err != nil {
-			s.logger.Warn("save FakeIP address pair: ", err)
-		}
-	}()
+	s.storage.FakeIPStoreAsync(address, domain, s.logger)
 	return address, nil
 }