### 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_
"Invalid parameter: The MessageGroupId parameter is required for FIFO topics"
                    )
                topic = self._get_topic(topic_arn, context)
                if topic.content_based_deduplication == "false":
                    if not all(
                        [
                            "MessageDeduplicationId" in entry
                            for entry in publish_batch_request_entries
                        ]
                    ):
                        raise InvalidParameterException(
                            "Invalid parameter: The topic should either have ContentBasedDeduplication enabled or MessageDeduplicationId provided explicitly",
                        )
            msg_ctx = SnsMessage.from_batch_entry(entry, is_fifo=is_fifo)
            message_contexts.append(msg_ctx)
            success = PublishBatchResultEntry(
                Id=entry["Id"],
                MessageId=msg_ctx.message_id,
            )
            if is_fifo:
                success["SequenceNumber"] = msg_ctx.sequencer_number
            response["Successful"].append(success)
        publish_ctx = SnsBatchPublishContext(
            messages=message_contexts,
            store=store,
            request_headers=context.request.headers,
        )
        self._publisher.publish_batch_to_topic(publish_ctx, topic_arn)
        return response
    def set_subscription_attributes(