feat: add install codesphere command and tests

[siherrmann]

Clickup task: https://app.clickup.com/t/869an04wc

[Copilot]

Pull Request Overview

This PR adds a new install codesphere command to the CLI tool with comprehensive test coverage. The main purpose is to provide functionality for installing Codesphere instances from package files on Linux amd64 platforms.

• Adds install codesphere subcommand with package extraction and installation logic
• Extends FileIO interface with ReadDir method and updates mocks accordingly
• Refactors Package struct to expose GetWorkDir method publicly

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
cli/cmd/install_codesphere.go	Implements new install codesphere command with extraction and installation logic
cli/cmd/install_codesphere_test.go	Comprehensive test suite for the new command functionality
cli/cmd/install.go	Updates install command to accept GlobalOptions and adds codesphere subcommand
cli/cmd/root.go	Reorganizes command structure and adds install codesphere to command tree
internal/installer/package.go	Makes getWorkDir method public (GetWorkDir) for external access
internal/util/filewriter.go	Extends FileIO interface with ReadDir method
internal/util/mocks.go	Adds mock implementation for new ReadDir method and reorders imports

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[NautiluX]

thanks for the PR! I think we need to identify a good way to test this on mac-based machines.

[NautiluX]

oh, please also provide a description to the PR, at minimum linking the CU card for paper trail ;)

[Copilot]

Pull Request Overview

Copilot reviewed 14 out of 15 changed files in this pull request and generated 4 comments.

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[NautiluX]

lgtm, just be aware the help output of the installation script won't be visible to users when running via OMS, so we need to make sure the descriptions explain the arguments