🎨 Palette: DX and state persistence improvements in sample app

[juankyc]

💡 What:

Improved the developer experience (DX) and reliability of the sample application by:

1. Making the ADB command copyable: Developers can now click the ADB logcat command at the top of the screen to copy it to their clipboard.
2. Adding State Persistence: The application now remembers if libhookee2.so has been loaded across configuration changes (like screen rotation), keeping the button in its disabled "Loaded" state.
3. UI Feedback: Added a Toast notification when the command is copied and updated the load button's text to reflect the library's state.

🎯 Why:

• Manually typing or selecting long ADB commands from a mobile UI is tedious. One-tap copy improves DX.
• In Android, Activity recreation on rotation would previously reset the "Load" button's state, leading to redundant clicks and confusing UI states since native library loading is generally irreversible in this context.

♿ Accessibility:

• Added android:contentDescription to the clickable ADB command TextView.
• Ensured the TextView is clickable and focusable for keyboard/screen reader navigation.
• Added android:foreground="?android:attr/selectableItemBackground" to provide visual focus and touch feedback.

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PR created automatically by Jules for task 9231652630102879114 started by @juankyc

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