Added an incomplete summary of current speedrun to demos

[betsruner]

The idea behind this feature is to add a summary of the splits of this speedrun to every demo in the speedrun.

There are two main reasons this is desirable:

1. When people submit chapter runs from their full game runs, those demos don't include a speedrun summary, which can be a substantial inconvenience.
2. It provides proof of Gold vs. IL. The only real difference between a Gold and an IL PB is whether it occurred during a run. Previously, there was no way to verify that someone's demo actually came from a run without requiring them to provide a potentially full run's worth of demos.

The reason for using a new demo data type is mainly to avoid overcomplicating MDP. If we reused the same data type, the output would become unreadable since every demo would be cluttered with a summary. To avoid this, MDP would have to guess which demo is the final one in a run, which is outside the scope of that project. By using a separate data type, we can offer two distinct config options, allowing users to toggle incomplete summaries and complete summaries independently.

[ThisAMJ]

lgtm