[Feature Request]: Improve onboarding experience for both humans and agents #26

• Build a landing page to explain the value proposition and core workflow of agent-task-loop.
• Add human-facing documentation for installation, configuration, and common usage patterns.
• Add an agent-facing skill that documents how agents should invoke and interact with the agent-task-loop CLI.

For the documentation site, we should host and deploy it on Vercel.

We should also consider using vercel-labs/zero-native as the foundation for building the site:
https://github.com/vercel-labs/zero-native