feat: update application icons and add marketing assets

- Replaced the application icon in package.json with a larger version for better visibility.
- Added a new logo image file `logo_larger.png` to the public directory.
- Introduced a Dockerfile for the marketing section to serve static files using Nginx.
- Created a new `index.html` file for the marketing site, featuring a responsive layout and sections for features and technology stack.

marketing/Dockerfile

@@ -0,0 +1,10 @@
+FROM nginx:alpine
+
+# Copy the public directory to nginx's html directory
+COPY public/ /usr/share/nginx/html/
+
+# Expose port 80
+EXPOSE 80
+
+# Start nginx
+CMD ["nginx", "-g", "daemon off;"]