Fastapi cleanup

[kreneskyp]

Description

This is the final-ish PR in the GraphQL -> FastAPI conversion. This PR converts the last couple bits that were still in use and deprecates graphql code and queries.

There are only a few remaining items using graphql:

• subscriptions / websockets: These will remain for now. GraphQL websockets work very cleanly so not replacing them just yet.
• Tasks: These views aren't in use so they weren't converted yet. May be done at a future point.

Changes

• new chat button and redirect now use FastAPI
• moved chat/graphql to chat/hooks

How Tested

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TODOs

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