playground: better readme and prerelease yacv-server

README.md

@@ -15,6 +15,8 @@ in a web browser.
 - Select any entity and measure bounding box size and distances.
 - Hot reloading while editing the CAD model (using the `yacv-server` package).
 - Fully-featured static deployment: just upload the viewer and models to your server.
+- Build123d playground! code and build your model fully inside the
+  browser: [demo](https://yeicor-3d.github.io/yet-another-cad-viewer/#pg_code_url=https://raw.githubusercontent.com/gumyr/build123d/refs/heads/dev/examples/toy_truck.py).
 
 ## Usage
 
@@ -32,4 +34,5 @@ demo [here](https://yeicor-3d.github.io/yet-another-cad-viewer/?preload=logo.glb
 - [cq-studio](https://github.com/ccazabon/cq-studio) provides an alternative workflow that detects file changes instead
   of relying on an interactive environment like Jupyter for hot-reloading.
   Uses the same backend and frontend behind the scenes.
-- [build123d-docker](https://github.com/derhuerst/build123d-docker/pkgs/container/build123d) provides docker images for Yet Another CAD Viewer and other projects, with automatic updates.
+- [build123d-docker](https://github.com/derhuerst/build123d-docker/pkgs/container/build123d) provides docker images for
+  Yet Another CAD Viewer and other projects, with automatic updates.

frontend/tools/PlaygroundStartup.py

@@ -8,7 +8,7 @@ await micropip.install("lib3mf")
 micropip.add_mock_package("py-lib3mf", "2.4.1", modules={"py_lib3mf": 'from lib3mf import *'})
 
 # Install the yacv_server package, which is the main server for the OCP.wasm playground; and also preinstalls build123d.
-await micropip.install("yacv_server")
+await micropip.install("yacv_server", pre=True)
 
 # Preimport the yacv_server package to ensure it is available in the global scope, and mock the ocp_vscode package.
 from yacv_server import *