Document build process and environment variables

[aygp-dr]

Issue Description

The repository lacks clear documentation about the build process and environment variables.

Current issues:

• CLAUDE.md mentions build commands (make for build) but there's no build target in the Makefile
• README.org doesn't clearly describe any build process
• While .env.sample is well-documented, README.org doesn't explain all environment variables' purposes
• Missing documentation about required environment setup

Proposed Changes:

1. Document the actual build process if one exists
2. Remove references to non-existent build commands
3. Add a section in README.org explaining important environment variables
4. Document dependencies and prerequisites more clearly
5. Add troubleshooting section for common environment issues

Impact:

Clear documentation about the build process and environment variables will make it easier for new users to get started with the project.