Add Terragon setup script for development environment initialization

[Roystbeef]

Summary

• Introduces a new setup script terragon-setup.sh to prepare the Terragon codebase for development
• Validates project structure and required files
• Checks for essential dependencies like Python3 and Git
• Provides guidance for starting a local development server

Changes

Setup Script

• terragon-setup.sh: Bash script that:
  • Ensures it is run from the project root by checking for index.html
  • Verifies presence of required files (index.html, css/styles.css, js/main.js, README.md)
  • Checks for Python3 installation and Git availability
  • Confirms if the project is a Git repository and shows current branch
  • Provides instructions to start a local development server using Python3
  • Offers development tips and project overview

Test plan

• Run the script from the project root and verify all checks pass
• Confirm error messages appear when required files or dependencies are missing
• Validate instructions for starting the development server are clear and accurate
• Ensure script exits on errors to prevent partial setup

This script streamlines the initial setup process for developers, ensuring a consistent environment and reducing setup errors.

🌿 Generated by Terry

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📎 Task: https://www.terragonlabs.com/task/12760a0f-10bf-46bf-a8ba-4dad53696328