refactor(docs repl): rewrite using minimal SW

The SW now only proxies, bunding is done by a worker per version

Author: wmertens

packages/docs/package.json

@@ -19,7 +19,7 @@
     "@mui/x-data-grid": "6.20.4",
     "@qwik-ui/headless": "0.6.7",
     "@qwik.dev/partytown": "0.11.2",
-    "@rollup/browser": "^4.35.0",
+    "@rollup/browser": "4.35.0",
     "@shikijs/colorized-brackets": "3.12.2",
     "@shikijs/langs": "3.12.2",
     "@shikijs/rehype": "3.12.2",
@@ -38,7 +38,6 @@
     "gray-matter": "4.0.3",
     "leaflet": "1.9.4",
     "magic-string": "0.30.17",
-    "memfs": "^4.17.0",
     "openai": "3.3.0",
     "prettier": "3.6.2",
     "prism-themes": "1.9.0",

packages/docs/public/repl/~repl-server-host.html

@@ -0,0 +1,76 @@
+# Qwik Docs REPL
+
+This folder contains the client-side REPL (Read-Eval-Print Loop) used in the Qwik docs site. The REPL lets users write and run Qwik/TypeScript code snippets in the browser, see results, and share runnable examples.
+
+This README gives a high-level overview of how the REPL is structured, what each area is responsible for, and some development notes and suggested improvements.
+
+---
+
+## High-level architecture
+
+The REPL is a browser-first system composed of three main parts:
+
+- Bundler subsystem (web-worker + helpers): transforms user code, resolves imports, bundles modules, and prepares runnable artifacts.
+- Service worker: Intercepts requests to `/repl/[id]/*` and messages the bundler subsystem (via BroadcastChannel) to get responses. This allows the REPL to work without a server.
+- UI (React/Qwik components + Monaco): editor, panels, console, options and controls that let users edit code and view outputs.
+
+The codebase keeps bundling and heavy work off the main thread by using a web worker script per Qwik version.
+
+## Key directories & files
+
+- `bundler/`
+  - `bundled.tsx` — provides the current development version of Qwik, so that the REPL can show the latest features, and it can work while developing offline.
+  - `bundler-registry.ts` — maintains the per-version Qwik WebWorkers.
+  - `bundler-worker.ts` — bundles and runs the REPL user code.
+  - `repl-instance.ts` — orchestration or single-instance logic for a REPL embed on a page.
+
+- `repl-sw.ts` and `register-repl-sw.ts`
+  - Service worker script and registration helper. The script is actually served via the route `/src/routes/repl/repl-sw.js/entry.ts`, which becomes the served path `/repl/repl-sw.js`.
+
+- `ui/`
+  - `editor.tsx`, `monaco.tsx` — Monaco editor wiring and editor UI glue.
+  - `repl-*.tsx` — UI components for console, input/output panels, tabs, share URL, version display, etc.
+
+## How it works
+
+1. The UI component (`ui/editor.tsx` + `ui/monaco.tsx`) presents a code editor and controls.
+2. When code is executed, the bundler subsystem is invoked. The UI posts a message to the bundler worker.
+3. The bundler worker (`bundler-worker.ts`) makes the client and SSR bundles, and executes `render()` from the `entry.ssr` to get the SSR result HTML.
+4. The UI also shows an iframe, loading `/repl/[id]/`.
+5. The service worker intercepts all requests and uses messages to get the bundle + html files from the worker.
+
+### Flow diagram
+
+- The iframe requests `/repl/[id]/`
+- The service worker intercepts and sends a message to the REPL instance
+- The REPL instance messages the bundler to bundle the user code
+- The bundler messages the REPL with the result
+- The REPL messages the service worker with the requested file
+- The service worker fullfils the request
+
+```mermaid
+flowchart TD
+  Iframe["Iframe - /repl/[replId]/"]
+  ServiceWorker["Service Worker (/repl/*)"]
+  ReplInstance["REPL instance"]
+  BundlerWorker["Bundler Worker"]
+
+  ReplInstance -->|REPL user code| BundlerWorker
+	BundlerWorker -->|ReplResult| ReplInstance
+  ServiceWorker -->|message: fetch pathname| ReplInstance
+  Iframe -->|HTTP request| ServiceWorker
+  ReplInstance -->|file contents| ServiceWorker
+  ServiceWorker -->|respond to iframe| Iframe
+```
+
+## Running the REPL
+
+The REPL is part of the docs site — start the docs dev server (project root):
+
+```bash
+pnpm docs.dev
+```
+
+Then visit `/playground`.
+
+- Resource limits & sandboxing: Running arbitrary user code in the browser can be risky — ensure sandboxed iframes and timeouts/limits for executed code to avoid locking the page.