### 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_
log_streams = aws_client.logs.describe_log_streams(logGroupName=log_group_name)[
                "logStreams"
            ]
            assert len(log_streams) == 1
            log_events = aws_client.logs.get_log_events(
                logGroupName=log_group_name,
                logStreamName=log_streams[0]["logStreamName"],
            )
            assert len(log_events["events"]) == 1
            # t
            with contextlib.suppress(ClientError):
                aws_client.logs.delete_log_group(logGroupName=log_group_name)
            return log_events
        sleep_time = 5 if is_aws_cloud() else 0.3
        events = retry(get_log_events, retries=10, sleep=sleep_time)
        # w
        # t
        msg = json.loads(events["events"][0]["message"])
        events["events"][0]["message"] = msg
        events["events"][0]["message"]["delivery"]["providerResponse"] = json.loads(
            msg["delivery"]["providerResponse"]
        )
        snapshot.match("delivery-events", events)