Refactor Memory with Prompt-tsx

[supreme-gg-gg]

One way to do this very basically is just use LanguageModelChatMessage.Assistant("message") but I doubt if we can get far with that...

Therefore I suggest (as well as VSCode officially) using their prompt-tsx which hopefully does not give me React trauma: https://code.visualstudio.com/api/extension-guides/prompt-tsx

[supreme-gg-gg]

I am in the process of carrying out this upgrade process. The first stage of the upgrade will replace ChatHistory and FileContext using code similar with their existing code sample (should be easy).

The second phase will commence in correspondence with tool use #27 since Prompt TSX supports tools officially now!