Create a better Lichess Local Engine app

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see:

• https://github.com/fitztrev/lichess-tauri/
• https://github.com/lichess-org/external-engine/blob/main/example-provider.py
• https://github.com/zamfofex/leela-lichess

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Some ideas:

• keep a log of the results so you can go back to them in the app
• cache stuff, so if the same position is requested, return the cached result before interrogating the engine
• multiple engines at the same time?