Bring the Econsult-family design tokens (see design-system-econsult.md)
into leistungsbilanz-ts and add a persistent sidebar for the projects
area, mirroring elt-planung-suite / Einsatz-Orga. The sidebar lists all
projects and, inside a project, jumps to its sections; the tree editor
stays sidebar-free since it needs the full width. The projects overview
page is decluttered to a single stacked column (create/import/global
devices) now that the project list lives in the sidebar.
Grovy311
jappel