✨ feat: implement mock data support with API interceptor and update documentation

AGENTS.md

@@ -13,16 +13,18 @@ Tibi CMS starter template — Svelte 5 SPA with esbuild, SSR via goja, and Playw
 ## Setup commands
 
 - Install deps: `yarn install`
-- Start dev (Docker): `make docker-up && make docker-start`
-- Start dev (local): `yarn dev`
+- Start dev: `make docker-up && make docker-start`
+- Start with mock data: set `MOCK=1` in `.env`, then `make docker-up && make docker-start`
 - Build frontend: `yarn build`
 - Build SSR bundle: `yarn build:server`
 - Validate types: `yarn validate`
 
 ## Development workflow
 
-- Default dev flow is Docker/Makefile: `make docker-up`, `make docker-start`, `make docker-logs`, `make docker-restart-frontend`.
-- Local dev is secondary: `yarn dev` for watch, `yarn build` and `yarn build:server` for production builds.
+- **Dev servers always run in Docker** — never use `yarn dev` or `yarn start` locally; web access only works through the Docker reverse proxy.
+- Docker/Makefile commands: `make docker-up`, `make docker-start`, `make docker-logs`, `make docker-restart-frontend`.
+- Local `yarn` is only for standalone tasks: `yarn build`, `yarn build:server`, `yarn validate`.
+- **Mock mode**: Set `MOCK=1` to run the frontend without a tibi-server. API calls are served from JSON files in `frontend/mocking/`. Enable in Docker via `MOCK=1` in `.env`, then `make docker-up && make docker-start`. Missing mock endpoints return 404.
 - Frontend code is automatically built by watcher and BrowserSync; backend hooks are automatically reloaded on change.
 - Read `.env` for environment URLs and secrets.
 - `webserver/` is for staging/ops only; use BrowserSync/esbuild for day-to-day dev.