* wip: astro config to use .ts instead of .mjs
* fix: remove invalid prop in astro config
* refactor: single source of truth for site url
* refactor: make minor updates due to astro.config.ts
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Co-authored-by: satnaing <satnaingdev@gmail.com>
Move theme switch js codes in Layout.astro file to external js file (toggle-theme.js). Update
.prettierignore to exclude the new toggle-theme.js file. Update base.css for new data-theme
attribute.