holix-studio-frontend-backend

## When to use You are in **Holix Studio** and the project has (or will have) **both**: - a **frontend** (Vite, Next, CRA, static SPA, etc.) on one listen port - a **backend** API (FastAPI, Express, Django, …) on another listen port Apply this skill **before** telling the user the app is ready, and whenever the frontend still points at `localhost` after both services are up. ## Goal The browser loads the frontend from Studio’s **public** preview URL (H2 subdomain or path proxy). From that browser context, `http://localhost:8000` is **the user’s machine**, not the Studio host. API calls must use the backend’s **real Studio public origin**. ## Mandatory workflow 1. Start backend and frontend under the **profile workspace** (`start_background_process` / project scripts). Keep the **project’s configured ports** (do not invent random ports). 2. Wait until both are healthy (listen + health check). 3. Resolve public origins via built-in MCP **`holix_studio`** (tools appear as `mcp_holix_studio_*`): - `open_preview_url(port=…)` for each service (user Browser + registers H2 when enabled) - `preview_origins` — map `port → origin` for the whole profile - `resolve_preview_origin_tool(port=BACKEND_PORT)` — single backend origin + siblings 4. Set the **frontend** API base to the **backend** `origin` from that response (not localhost). 5. If the backend enforces CORS, allow the **frontend** public origin (from `origins` / `open_preview_url` for the FE port). 6. Restart the f...