Update all four Beszel widgets to use extracted shared hooks, chart
helpers, colors, and formatters. Fix chart data regressions: restore
byte-to-GB conversion for memory/disk, use raw byte values for diskIO
instead of incorrect multiplication, and use ns/nr fields for network
instead of the optional b field.
Add drag-and-drop performance fixes: disable pointer events and
WebSocket subscriptions during edit mode to prevent re-renders while
dragging widgets on the board.
Thomas Camlong
6b1cc0fd6b