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-is-plain-obj-C1gvLhAf.js

@@ -0,0 +1 @@
+function e(t){if(typeof t!="object"||t===null)return!1;const o=Object.getPrototypeOf(t);return(o===null||o===Object.prototype||Object.getPrototypeOf(o)===null)&&!(Symbol.toStringTag in t)&&!(Symbol.iterator in t)}export{e as i};