feat: reference extended base image in install-config

[siherrmann]

Clickup task: https://app.clickup.com/t/869an09dr

[Copilot]

Pull Request Overview

This PR implements functionality to reference extended base images in the install-config by adding support for building and pushing custom workspace images. The changes introduce new file parsing capabilities, image management abstractions, and CLI commands for handling container images.

Key Changes:

• Added configuration parsing for YAML files and OCI image indexes
• Introduced ImageManager interface with docker/podman support for loading, building, and pushing images
• Created new build images command for building and pushing container images based on configuration

Reviewed Changes

Copilot reviewed 21 out of 21 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
internal/system/image.go	New ImageManager implementation supporting docker/podman operations
internal/system/mocks.go	Generated mocks for ImageManager interface
internal/installer/files/config_yaml.go	Config parsing for YAML with image and flavor definitions
internal/installer/files/oci_image_index.go	OCI image index parsing and name extraction
internal/installer/config.go	ConfigManager implementation for parsing configs and OCI indexes
internal/installer/package.go	Refactored Package to use private fileIO with accessor method
cli/cmd/install_codesphere.go	Updated to load and build workspace images during installation
cli/cmd/extend_baseimage.go	Refactored to use new ConfigManager and ImageManager interfaces
cli/cmd/build_images.go	New command for building and pushing images from config
cli/cmd/build.go	New build command group
go.mod	Moved gopkg.in/yaml.v3 from indirect to direct dependency

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[NautiluX]

thanks! Sorry for the delay, finally got to reading it :)

[Copilot]

Pull Request Overview

Copilot reviewed 68 out of 69 changed files in this pull request and generated 3 comments.

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[NautiluX]

Thanks @siherrmann ! This PR is huge now, let's please try to iterate on smaller features or parts of them in the future. I'll approve this now so we can manually test and iterate on the commented things later.