feat(integration): Integrated backend and frontend through websocket

Added a main webpage to web/app with a navbar to control login/logout and add/select/remove a database to be queried. Restructured the main dashboard to use tailwindcss. Ported the websockets and broker implementation to V1 and tied all components (schema, querybuilder, and visualizer) together. Merge branch 'feat/websocket' into 'main' See merge request !24

Solves #21