feat: auto-fallback to default bind IP when invalid bind address detected

When a forward service is updated with a bind IP that doesn't exist on the
host network interfaces, the system now automatically falls back to the
default bind address (listening on all interfaces) instead of failing.

- Added syncForwardServicesWithWarnings to collect fallback warnings
- Implemented fallbackForwardPortToDefaultBind for graceful degradation
- Added UpdateForwardPortBindIP repository method to persist fallback
- Enhanced error detection for 'cannot assign requested address' errors
- Frontend displays warning toasts when fallback occurs
- Added comprehensive unit tests for new error detection functions

vite-frontend/src/pages/forward.tsx

@@ -1419,6 +1419,18 @@ export default function ForwardPage() {
       }
 
       if (res.code === 0) {
+        const warningItems = Array.isArray((res as any).data?.warnings)
+          ? (res as any).data.warnings
+              .map((item: unknown) => (typeof item === "string" ? item.trim() : ""))
+              .filter((item: string) => item)
+          : [];
+
+        warningItems.forEach((warning: string) => {
+          toast(warning, {
+            icon: "⚠️",
+            duration: 5000,
+          });
+        });
         toast.success(isEdit ? "修改成功" : "创建成功");
         setModalOpen(false);
         loadData();