[Feature Request] Hotkey to enable/disable CelesteTAS

Similarly to other mods, offering a hotkey to toggle all mod functionality would make it easier to switch from a speedruntool + celestetas + whatever else setup to a vanilla-ish setup without having to actually restart into vanilla.
This is useful for immersion or when you just want to play without hitboxes and camera tweaks.
Currently, toggling CelesteTAS can only be achieved by going into mod options and toggling CelesteTAS from there, which is kinda tedious.

thx :D

Start by locating the existing CelesteTAS toggle in mod options and checking how other mods register hotkeys. Trace the current enable/disable path, then verify that the new hotkey switches all mod functionality between CelesteTAS-enabled and vanilla-like behavior without requiring a restart.

Written by the indexing model from the issue text.