Port spans now pick up the connection's actual color for border and a
light tint for background via inline styles. The .connected CSS class
only ups the border width to 2px for emphasis. Applied to _port_list.html
shared partial and wall_sockets.html inline rendering.
Grid sections for Racks and Devices now show a dashed 'No X yet' message
when the collection is empty, using Go template {{else}} blocks. CSS
styles the placeholder with muted text and a dashed border.
Replaced independent flex columns with a single table where each rack
unit is a <tr> containing both front and back content. Row heights now
stay locked together regardless of device name length. Device-start
rows get a top border and surface background for visual grouping.
Joca