android : Apply chat template

[Dhruvanand24]

Description

This PR introduces foundational changes to enhance chat template functionality in the Llama Android project. While the core functionality has been implemented, integration with the main application flow is pending and will be addressed in future updates.

1. Added JNI Support:

   • Integrated JNI for applying chat templates in llama-android.cpp.
   • This implementation processes a list of messages in a structured format for better templating capabilities.

2. Updated LlamaAndroid.kt:

   • Added a new function to handle chat templates.
   • This function accepts a list of maps (List<Map<String, String>>) for structured message handling.

3. Refactored MainViewModel.kt:

   • Modified messages to be a list instead of a string:

     var messages by mutableStateOf(listOf<Map<String, String>>())

4. Pending Integration:

   • The new applyChatTemplate function is created but not yet invoked in the application flow.
   • Future updates will include logic to call this function as follows:

     llamaAndroid.send(llamaAndroid.applyChatTemplate(messages))

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Benefits

• Enhanced Structure: Enables structured message handling for better scalability and maintainability.
• Increased Flexibility: Supports dynamic application of chat templates.
• Future-Proof: Lays the groundwork for more sophisticated chat interactions.

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Testing

• Verified JNI integration for chat template processing.
• Ensured compatibility with the updated MainViewModel.kt.
• Basic functionality of applyChatTemplate tested with sample data.

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To-Do

• Integrate applyChatTemplate into the main application flow.
• Add unit tests for applyChatTemplate in LlamaAndroid.kt.
• Conduct integration testing for JNI enhancements.

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Reviewer Notes

• Feedback on structuring the pending integration logic is welcome.
• Suggestions for improving the applyChatTemplate function are appreciated.
• Insights on optimizing JNI interactions for performance would be valuable.

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