feat: 增强POST /:key处理，支持空值和JSON格式验证

routes/kv-token.js

@@ -354,9 +354,21 @@ router.post(
 
         const deviceId = res.locals.deviceId;
         const { key } = req.params;
-        const value = req.body;
+        let value = req.body;
 
+        // 处理空值，转换为空对象
+        if (value === null || value === undefined || value === '') {
+            value = {};
+        }
 
+        // 验证是否能被 JSON 序列化
+        try {
+            JSON.stringify(value);
+        } catch (error) {
+            return next(
+                errors.createError(400, "无效的数据格式")
+            );
+        }
 
         // 获取客户端IP
         const creatorIp =
@@ -366,7 +378,7 @@ router.post(
             req.connection.socket?.remoteAddress ||
             "";
 
-        const result = await kvStore.upsert(deviceId, key, value, creatorIp);
+        const result = kvStore.upsert(deviceId, key, value, creatorIp);
 
         // 广播单个键的变更
         const uuid = res.locals.device?.uuid;