feat: initialize rt-smooth-scroll package with esbuild for smooth scrolling functionality

- Created package.json and package-lock.json for project setup
- Added build script using esbuild to compile and minify the source code
- Implemented smooth scrolling logic in src/index.js with customizable options
- Included default configuration attributes for easy integration
- Set up instance management for multiple smooth scrolling instances

Author: Druhin13

.gitignore

@@ -0,0 +1,4 @@
+node_modules
+.DS_Store
+dist/*.map
+dev