feat: add theme management with light and dark modes

- Implemented a new composable `useTheme` for managing theme state.
- Added functions to read and write theme preference to local storage.
- Applied theme styles to the DOM based on user preference.
- Introduced a toggle function to switch between light and dark themes.

refactor: enhance copilot plugin functionality

- Improved request handling with sequence and document versioning.
- Refactored ghost text handling to improve clarity and efficiency.
- Updated markdown insertion logic to handle parsed content more robustly.
- Enhanced error handling and logging for better debugging.

style: update global styles for light and dark themes

- Defined CSS variables for light and dark themes to streamline styling.
- Improved overall styling consistency and responsiveness.
- Added transitions for smoother theme changes and interactions.

.build-check/assets/vendor-unist-util-visit-8PRsQcuP.js

@@ -0,0 +1 @@
+import{v}from"./vendor-unist-util-visit-parents-BHoKBdZX.js";function h(l,n,e,u){let t,f,i;typeof n=="function"&&typeof e!="function"?(f=void 0,i=n,t=e):(f=n,i=e,t=u),v(l,f,a,t);function a(c,d){const o=d[d.length-1],p=o?o.children.indexOf(c):void 0;return i(c,p,o)}}export{h as v};