Update the site for MPCkit 0.5.3
What changed
public/index.html:
- the badge says Version 0.5.3;
- the Download note says "The 0.5 releases are betas for testing", as the app's README does, so it stays right for later 0.5.x releases;
- the image descriptions name pads "A3" and "A1", and the image sizes match the new screenshots.
public/images/pads.png, sequences.png: new screenshots of 0.5.3 from the Windows build, with the window title "MPCkit" and the new "A1" pad labels. The local path in the status bar ("Loaded C:\Users\…") was painted out.
Notes
- Source links and downloads are unchanged; they move to GitHub in a later PR.
Testing
- Served
public/ locally and checked desktop and mobile screenshots.