fix(webui): use table-layout fixed so table shrinks with container when action panel...

fix(webui): use table-layout fixed so table shrinks with container when action panel opens

Replace min-width: 1280px + table-layout: auto with table-layout: fixed.
Auto layout ignores width: 100% and expands based on content, causing
the table to overflow behind the action panel. Fixed layout respects
the container width and distributes columns equally. Add overflow:
hidden on charging-stations-container as belt-and-suspenders clip.