Give operator panels the whole screen width

A panel was squeezed into the 640px form column, so a two-camera adjustment screen or a wide synoptic could not use the station's screen.

• Added full-width panels: a phase or run panel now takes the whole screen, in the kiosk and in the browser, while regular forms keep their column.
• Improved panel screens: the title and the Continue button stay in the form's column, so they no longer move between a panel phase and a form phase.
• Fixed oversized drawings: an SVG without a set height now stays on screen, and panels can set their own size in CSS.