Plugin Variables Fix

When building Plugins in Advanced mode, users have the option of including a wide range of variables in their custom instructions. Recently we made a few new variables available, including {{ scene_summary }} and {{ character_beats }}. While those variables worked flawlessly on *new* Plugins, there was an issue preventing them from working on older Plugins that predated them. We've resolved that issue, and **all available variables now work on Plugins regardless of when they were originally built**.