Under the hood
Slash-command dispatch code was renamed internally with no behavior change found
What
A large section of code handling local and prompt slash-command execution, including deferring commands to the engine, stacked skills, and UserPromptSubmit hook handling (which runs when you submit a prompt, before Claude processes it), was restructured under new minified variable names. The underlying deferSlashToEngine/engineDeferredSlash mechanism it relies on already existed previously.
Why
No functional change was found in this code; it appears to be a cosmetic rename from the build process.