refactor: clean up codebase by removing redundant comments

Remove unnecessary JSDoc comments and redundant explanations from components, types, and data files. Simplify code structure while maintaining functionality.

Clean up language handling logic in components by removing redundant comments and simplifying state management. Move type imports to dedicated type import statements where applicable.

src/lib/data/personal-info.ts

@@ -1,13 +1,4 @@
-/**
- * Personal information data module
- * Contains all personal information used throughout the site
- */
 import type { PersonalInfo } from '@/types';
-
-/**
- * Personal information data
- * This data is used in various components like Header, Footer, and About sections
- */
 export const personalInfo: PersonalInfo = {
   name: "Joy Zhao",
   location: "China",