Implementing logic to handle reducing the length of messages that exceed the provider's max length. At this stage it should just truncate the message when it hits the max length.

Couple of possibilities:

1. Just add a simple truncate
2. Add the simple truncate as a part of the API and add it as a default, and allow gateways to extend and give their own allowed length.

This requirement was initially added in MDL-83518, but this tracker was created to make sure we follow the right approach and get the work the done independently without having to block the major ones.