Light UI scheme. Bigger fonts.

v1.50.5

Features

• Light theme — the dashboard and login page gain a light theme alongside the dark "Engineer's Console" field. It follows the OS (prefers-color-scheme) by default; a header toggle cycles System → Light → Dark and persists the choice to localStorage, applied before first paint so there is no flash. It is built by re-pointing the existing :root color tokens — signal colors switch to AA-verified darkened variants on the light field, while the embedded terminal stays dark — and the logo is now transparent so it reads cleanly on either field.
• Larger dashboard type scale — 68 hardcoded px font sizes were replaced with six semantic rem tokens (--text-2xs…--text-xl), raising every tier ~+2px (body 13→15px, titles 15→17px, header 20→23px) for readability at density. (#63)
• Note dialog Delete button — the environment note editor now has an explicit Delete action. (#63)