### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

SNS allows for the publishing of messages to an SMS destination with a phone number. Those messages are logged and stored in the `SnsStore`, but there is no way to retrieve them for verification. The request here is to expose a new endpoint which returns SMS messages from the store, similar to the one made available to retrieve email messages sent via SES.

### 🧑‍💻 Implementation

The `SNSServicePlatformEndpointMessagesApiResource` class makes endpoints available for accessing platform endpoint messages sent via SNS. A similar resource class could be implemented to provide new endpoints for accessing SMS messages.

Given that interaction platform endpoint messages is exposed at the path `/_aws/sns/platform-endpoint-messages`, SMS message interaction would presumably be exposed at `/_aws/sns/sms-messages`. A `GET` endpoint could accept an optional `phoneNumber` query parameter to filter messages based on the destination phone number.

```python
class SNSServiceSMSMessagesApiResource:
  @route(sns_constants.SMS_MSGS_ENDPOINT, methods=["GET"])
    def on_get(self, request: Request):
      account_id = #...
      region = #...
      filter_phone_number = request.args.get("phoneNumber")
      # get store; conditionally filter messages based on filter_phone_number
```

### Anything else?

_No response_
self, sns_create_topic, sqs_create_queue, sns_create_s, snapshot, aws_client
    ):
        fifo_topic_name = f"topic-{short_uid()}.fifo"
        topic_arn = sns_create_topic(Name=fifo_topic_name, Attributes={"FifoTopic": "true"})[
            "TopicArn"
        ]
        with pytest.raises(ClientError) as e:
            aws_client.sns.publish_batch(
                TopicArn=topic_arn,
                BatchRequestEntries=[
                    {
                        "Id": "1",
                        "Message": "Test message without Group ID",
                    }
                ],
            )
        snapshot.match("no-group-id", e.value.response)
        with pytest.raises(ClientError) as e:
            aws_client.sns.publish_batch(
                TopicArn=topic_arn,
                BatchRequestEntries=[
                    {"Id": f"Id_{i}", "Message": "Too many messages"} for i in range(11)
                ],
            )
        snapshot.match("too-many-msg", e.value.response)
        with pytest.raises(ClientError) as e:
            aws_client.sns.publish_batch(
                TopicArn=topic_arn,
                BatchRequestEntries=[