v0.5.1

Changed

• The documentation site now opens in light mode by default.
  The light/dark toggle in the sidebar still works and still remembers your choice per browser.

Fixed

• The footer's "What's new" panel no longer shows an empty
  "Unreleased" heading above the current release notes.
• First launch on a fresh install no longer shows a
  connection-refused page. run.bat now waits for the local server
  to be ready before opening your browser, instead of opening it
  after a fixed 4-second delay. On a cold first launch the server
  can take 10–15 seconds to start (Python and Dash have to load); the
  browser now opens at the moment the page is actually available, so
  there is no error page to refresh past. Subsequent launches are
  unchanged — the wait is essentially zero once everything is warm.