docs(agent): add in_memory_cache_capacity options in agent

For [TS-5737](https://jira.taosdata.com:18080/browse/TS-5737)

docs/en/14-reference/01-components/05-taosx-agent.md

@@ -14,6 +14,7 @@ The default configuration file for `Agent` is located at `/etc/taos/agent.toml`,
 - `token`: Required, the Token generated when creating `Agent` in `Explorer`.
 - `instanceId`: The instance ID of the current taosx-agent service. If multiple taosx-agent instances are started on the same machine, it is necessary to ensure that the instance IDs of each instance are unique.
 - `compression`: Optional, can be configured as `true` or `false`, default is `false`. If set to `true`, it enables data compression in communication between `Agent` and `taosX`.
+- `in_memory_cache_capacity`: Optional, signifies the maximum number of message batches that can be cached in memory and can be configured as a positive integer greater than zero. The default value is set at 64.
 - `log_level`: Optional, log level, default is `info`. Like `taosX`, it supports five levels: `error`, `warn`, `info`, `debug`, `trace`. Deprecated, please use `log.level` instead.
 - `log_keep_days`: Optional, the number of days to keep logs, default is `30` days. Deprecated, please use `log.keepDays` instead.
 - `log.path`: The directory where log files are stored.
@@ -45,6 +46,10 @@ As shown below:
 #
 #compression = true
 
+# In-memory cache capacity
+#
+#in_memory_cache_capacity = 64
+
 # log configuration
 [log]
 # All log files are stored in this directory

docs/zh/14-reference/01-components/05-taosx-agent.md

@@ -12,7 +12,8 @@ sidebar_label: taosX-Agent
 - `endpoint`: 必填，`taosX` 的 GRPC 服务地址。
 - `token`: 必填，在 `Explorer` 上创建 `Agent` 时，产生的 Token。
 - `instanceId`：当前 taosx-agent 服务的实例 ID，如果同一台机器上启动了多个 taosx-agent 实例，必须保证各个实例的实例 ID 互不相同。
-- `compression`: 非必填，可配置为 `ture` 或 `false`, 默认为 `false`。配置为`true`, 则开启 `Agent` 和 `taosX` 通信数据压缩。
+- `compression`: 非必填，可配置为 `true` 或 `false`, 默认为 `false`。配置为`true`, 则开启 `Agent` 和 `taosX` 通信数据压缩。
+- `in_memory_cache_capacity`: 非必填，表示可在内存中缓存的最大消息批次数，可配置为大于 0 的整数。默认为 `64`。
 - `log_level`: 非必填，日志级别，默认为 `info`, 同 `taosX` 一样，支持 `error`，`warn`，`info`，`debug`，`trace` 五级。已弃用，请使用 `log.level` 代替。
 - `log_keep_days`：非必填，日志保存天数，默认为 `30` 天。已弃用，请使用 `log.keepDays` 代替。
 - `log.path`：日志文件存放的目录。
@@ -44,6 +45,10 @@ sidebar_label: taosX-Agent
 #
 #compression = true
 
+# In-memory cache capacity
+#
+#in_memory_cache_capacity = 64
+
 # log configuration
 [log]
 # All log files are stored in this directory