🎨 Palette: Improve sample app interactivity and state feedback

[juankyc]

💡 What:

• Updated the "Load libhookee2.so" button to disable itself and update its text upon successful loading, providing clear state feedback.
• Made the ADB command TextView clickable and copyable to the clipboard, with a Toast confirmation.
• Added a ripple effect (selectableItemBackground) to the ADB command TextView to signal interactivity.
• Upgraded Gradle to 8.5 and AGP to 8.2.2 to resolve build issues in the Java 21 environment.

🎯 Why:

• Users (developers) need clear feedback when native libraries are loaded to avoid redundant actions.
• Manual typing of long ADB commands is error-prone; a copyable command improves the developer experience.
• The dev environment uses Java 21, which is incompatible with the original Gradle 7.5/AGP 7.4.2 setup.

♿ Accessibility:

• Interactive TextView is now focusable and clickable.
• State changes (loading) are clearly reflected in the UI and via Toasts.

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PR created automatically by Jules for task 10136058926700650078 started by @juankyc

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