Add activity feed API

[sungdomo]

TL;DR

Added a basic Express server with a mock activity feed endpoint.

What changed?

Created a new server.js file in the graphite-demo directory that:

• Sets up an Express server running on port 3000
• Defines a mock activity feed with sample data
• Implements a GET endpoint at /feed that returns the activity feed data as JSON

How to test?

1. Install dependencies: npm install express
2. Start the server: node graphite-demo/server.js
3. Access the endpoint in your browser or with curl: curl http://localhost:3000/feed
4. Verify that the response contains the mock activity feed data

Why make this change?

This provides a simple backend API for the graphite demo application to fetch activity feed data, enabling frontend development without requiring a full backend implementation. The mock data allows for testing the activity feed display functionality.

[sungdomo]

• Add activity feed API #1 👈 (View in Graphite)
• main

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