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-micromark-util-chunked-DrRIdSP-.js

@@ -0,0 +1 @@
+function u(h,n,c,f){const l=h.length;let p=0,e;if(n<0?n=-n>l?0:l+n:n=n>l?l:n,c=c>0?c:0,f.length<1e4)e=Array.from(f),e.unshift(n,c),h.splice(...e);else for(c&&h.splice(n,c);p<f.length;)e=f.slice(p,p+1e4),e.unshift(n,0),h.splice(...e),p+=1e4,n+=1e4}function g(h,n){return h.length>0?(u(h,h.length,0,n),h):n}export{g as p,u as s};