Qt AI Assistant support

What

• Qt Creator shall enable Qt AI Assistant to provide intuitive visualization and interactions with the responses from the LLM. 
• Qt Creator shall provide support for creating the "Agentic AI" showcase to be presented in the Qt World Summit 2025.

Why

• Table stakes. This functionality is provided by competing AI integrations. 
• Provide a convincing presentation and demonstration as continuity beyond current model.

Dependencies

• Qt AI Assistant project
• Spyrosoft

User stories / acceptance criteria

• As a developer, I want to see how LLM's suggestions would affect my code and accept changes I see as beneficial
  • whenever code is being suggested through an prompt in the inline prompt window, then the code must displayed showing the differences.
  • the software developer shall be able to accept or decline all changes by pressing corresponding buttons

Tasks

• Scoping: Define the required changes for the diffview implementation and create tasks according to that plan. 
• Scoping: Define the required changes for the agentic AI and create tasks according to that plan.
• ...