Add evaluation quickstart to README
Add an evaluation quickstart to the README. This should be a very concise quickstart targeted at people who discover this repository and want to get the software running as quickly as possible to see what it does. The main focus is to be able to see the preview site to evaluate the UI. The evaluation quickstart should not have any detailed explanations or backstory. It should read more like a recipe. The detailed information belongs in the formal quickstart found in the documentation.
The evaluation quickstart should cover:
- The list of prerequisites (what's needed)
- Preparing the environment (install / init commands)
- Launch the preview (typical usage)
- How / where to view the output (what to expect)