Implement OS color scheme auto-detection for new users (#302761)

* Implement auto-detect color scheme feature for new users and update related services

* Add OS color-scheme auto-detection support for new users

Co-authored-by: Copilot <[email protected]>

* Add assertions to verify color scheme detection for high contrast themes

Co-authored-by: Copilot <[email protected]>

* Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <[email protected]>

* Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <[email protected]>

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Co-authored-by: mrleemurray <[email protected]>
Co-authored-by: Copilot <[email protected]>
Co-authored-by: Copilot Autofix powered by AI <[email protected]>