Support reinstall in check command

[krisl]

No description provided.

[Copilot]

Pull Request Overview

This PR refactors the rosdep codebase to support the --reinstall option in the check command by extracting common dependency resolution logic into a shared function. The main changes involve separating dependency resolution from installation checking and modifying the RosdepInstaller class to work with pre-resolved dependencies.

• Extracts dependency resolution logic into a shared _resolve_dependencies function
• Modifies RosdepInstaller to accept pre-resolved dependencies instead of performing resolution internally
• Updates the dependency resolution algorithm in RosdepLookup.resolve_all to use a flattened approach

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/rosdep2/main.py	Extracts _resolve_dependencies function and refactors command_check and command_install to use shared logic
src/rosdep2/installers.py	Removes lookup dependency from RosdepInstaller constructor and modifies get_uninstalled to accept pre-resolved dependencies
src/rosdep2/lookup.py	Refactors dependency resolution algorithm to use a flattened queue-based approach
test/test_rosdep_installers.py	Updates tests to reflect the new RosdepInstaller API changes

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