Migrate Prototype for Backend+UI

[ChristianLempa]

Summary

Migrate the existing prototype code for a backend/frontend application into this repository.

Goal

Add a backend and UI application based on:

• Go for the backend
• Svelte for the frontend/UI

The existing Python CLI must remain intact and continue to work as it does today. The new backend/frontend application should live alongside the CLI rather than replacing it.

Scope

• Bring the prototype backend code into the repository.
• Bring the prototype Svelte UI code into the repository.
• Define a clean repository structure for CLI, backend, and frontend code.
• Ensure the CLI entry points and current workflows remain functional.
• Add basic local development instructions for running the backend and frontend.
• Add any necessary build/test configuration for the new components.

Acceptance Criteria

• The current CLI still runs and passes its existing tests.
• Backend and frontend code are committed in a clearly separated structure.
• Local development workflow is documented.
• The backend/frontend can be developed and run without disrupting CLI usage.