🔧 chore(config): add .env file to gitignore
- update .gitignore to exclude .env file containing environment variables
✨ feat(server): add dotenv configuration support
- import dotenv/config to load environment variables from .env file
✨ feat(frontend): conditionally load alicdn interaction script
- add alivc-im.iife.js script for non-admin pages
- only load script when URL does not start with '/admin'