[Update] Plugins(VRCT Subtitles as testing one): Provide-able store and functions from main app.

src-ui/app/main_page/main_section/MainSection.jsx

@@ -8,7 +8,6 @@ import { LanguageSelector } from "./language_selector/LanguageSelector";
 import { useStore_IsOpenedLanguageSelector } from "@store";
 import { useLanguageSettings } from "@logics_main";
 import { useEffect } from "react";
-import { SubtitleSystemContainer } from "./subtitle_system_container/SubtitleSystemContainer";
 
 import { PluginHost } from "./PluginHost";