Add Debian package build target to Earthfile

[arodage]

Merge Checklist

All boxes should be checked before merging the PR

• [] The changes in the PR have been built and tested
• [] Ready to merge

Description

This PR adds a new +deb target to the Earthfile that creates a production-ready Debian package for the OS Image Composer tool. The package follows the Filesystem Hierarchy Standard (FHS) and Debian packaging best practices, making it easy to distribute and install the tool on Ubuntu/Debian systems.

Key Changes:

• Added parameterized +deb target to Earthfile with configurable VERSION and ARCH arguments
• Package includes compiled binary, configurations, example templates, and documentation
• Follows FHS standards with proper directory structure (/etc, /usr/local/bin, /usr/share)
• Output location changed to dist/ directory for cleaner project organization
• Added comprehensive installation, verification, and uninstallation instructions to README.md
• Includes CLI specification document in package documentation

Package Layout:

• Binary: /usr/local/bin/os-image-composer
• Configuration: /etc/os-image-composer/ (user-editable)
• Examples: /usr/share/os-image-composer/examples/ (read-only templates)
• Documentation: /usr/share/doc/os-image-composer/ (README, LICENSE, CLI spec)

Usage:

# Build package
earthly +deb --VERSION=1.0.0 --ARCH=amd64

# Install package
sudo apt install ./dist/os-image-composer_1.0.0_amd64.deb

Any Newly Introduced Dependencies

How Has This Been Tested?

Build package:

Install package on ubuntu machines:

Verify installation:

Uninstall:

[Copilot]

Pull Request Overview

This PR introduces Debian package support for OS Image Composer, enabling easier distribution and installation on Ubuntu/Debian systems. The implementation follows Filesystem Hierarchy Standard (FHS) and Debian packaging best practices.

Key Changes:

• Added parameterized +deb target in Earthfile for building production-ready Debian packages
• Introduced comprehensive installation documentation in README.md covering build, install, verify, and uninstall workflows
• Added experimental build_oic_deb_package() function in validate.sh (appears to be legacy/test code)

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
Earthfile	Implements new +deb target with FHS-compliant directory structure, configurable VERSION/ARCH parameters, and artifact output to dist/ directory
README.md	Adds complete Debian package installation section with build instructions, verification steps, package contents overview, and uninstallation commands
validate.sh	Adds build_oic_deb_package() function for building basic Debian packages (appears to be experimental/legacy code)

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[magerstam]

I think there are more dependencies we need to add unify, mmdebbootstrap
License information has to be captured in metadata

[arodage]

I think there are more dependencies we need to add unify, mmdebbootstrap License information has to be captured in metadata

Right, we need to add the dependencies and we are copying the LICENSE file to the doc directory but as per deb package standards, we need the following:

[arodage]

@magerstam @srmungar
We need different defaults in /etc/os-image-composer/os-image-composer.yml
For example, config can not be ./config but /etc/os-image-composer/config/
Not sure what should be defaults for cache_dir work_dir and temp_dir

[magerstam]

LGTM