Fix android build on Windows, start_apk function and Kotlin linking

[enfipy]

Objective

• Build for android was failing on Windows because of the Path display.
• Kotlin linking was incorrect.
• Function start_apk didn't launch the Application if it was built with Gradle.
• Default command crossbundle build android actually doesn't build apk.
• Cargo Metadata and Gradle tests were failing.

Solution

• Use Path with Debug formatting.
• Use @JvmStatic for Kotlin external functions.
• Add an argument to the start_apk function to specify the Activity to launch.
• Launch the gradle build command at the end of the crossbundle build command.
• Fix tests test_cargo_metadata and test_build_gradle.

Changelog

Important: This change updates all libraries to the 0.1.6 version.