A utility class that can be used by the application to help fulfill dynamic statements.
Dynamic statements are statements configured for the application on the Slang Console, with
placeholders for dynamic information that can be fulfilled at intent resolution time.
For example, let's consider a hypothetical intent called current_time with the following dynamic
"Hello $$user! The time is now $time"
Here, $$user is an app property, and $time is an entity value, neither of which is known at
If the application has set an application property with key "user" and value to be the name of
the user, whenever an intent of type current_time is resolved by Slang, it will replace $$user
with the name of the user and the $time with the resolved entity value.