only surfacing username, and not userID, and username should be shown in UI

standardize fetch with cookie-based auth call

Inner query in JSON format fully reworked. The interface was reworked to use entity attributes as part of query logic. Handle inner logic and types fully reworked for better type-checking and future-proofing. Includes logic in query building, parsing, and execution.
Logic pills can be created from the handle drop and from the side panel.

Solves #42 and #53

Replaces the custom made auth-backend (auth-gateway) with its token logic and complexity
with established open-source FIPS 140-2 compliant authentication solution.
Current code uses newly deployed keycloak within kind deployment script,
but some todos are left and should be further developed.
Does not use auth-gateway anymore for authentication,
only as a proxy to extract authorization and user information from token for downstream apis.

solves #28

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.

Solves #21