Add support for adaptive and themed icons on android (#14223)

* add support for adaptive icons

* fix

* small cleanup

* combine android_bg and android_fg when specified

* Update crates/tauri-cli/src/icon.rs

Co-authored-by: Fabian-Lars <github@fabianlars.de>

* add scale option

* properly generated rounded icons

* covector, clippy

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Co-authored-by: Lucas Nogueira <lucas@tauri.app>
Co-authored-by: Fabian-Lars <github@fabianlars.de>