style(frontend): grundlegendes Redesign (Design-System, Farben, Typografie)

Neues Design-System: warme Honig-/Wachs-Farbpalette (Amber-Primaer,
Salbeigruen-Sekundaer) statt Standard-Graustufen, Space Grotesk fuer
Ueberschriften, Inter fuer Fliesstext, IBM Plex Mono fuer Codes/IDs.
Card-Komponente mit weicher Schattierung statt Ring, neuer
Badge-Warning-Variante und statusTone()-Helper fuer semantische
Status-Farben (Voelker/Honigchargen). Navigation umgebaut: aktiver
Link-Zustand, Hexagon-Markenzeichen, "Mehr"-Dropdown fuer Admin-Links.
Dashboard-Kacheln mit Icons/Farbakzenten, Login-Seite mit dezentem
Waben-Hintergrundmuster als wiederkehrendes Signature-Element.

ApiCore-Frontend/src/components/ui/badge.tsx

@@ -14,6 +14,8 @@ const badgeVariants = cva(
           "bg-secondary text-secondary-foreground [a]:hover:bg-secondary/80",
         destructive:
           "bg-destructive/10 text-destructive focus-visible:ring-destructive/20 dark:bg-destructive/20 dark:focus-visible:ring-destructive/40 [a]:hover:bg-destructive/20",
+        warning:
+          "bg-warning/15 text-warning-foreground focus-visible:ring-warning/30 [a]:hover:bg-warning/25",
         outline:
           "border-border text-foreground [a]:hover:bg-muted [a]:hover:text-muted-foreground",
         ghost:

ApiCore-Frontend/src/components/ui/card.tsx

@@ -12,7 +12,7 @@ function Card({
       data-slot="card"
       data-size={size}
       className={cn(
-        "group/card flex flex-col gap-(--card-spacing) overflow-hidden rounded-xl bg-card py-(--card-spacing) text-sm text-card-foreground ring-1 ring-foreground/10 [--card-spacing:--spacing(4)] has-data-[slot=card-footer]:pb-0 has-[>img:first-child]:pt-0 data-[size=sm]:[--card-spacing:--spacing(3)] data-[size=sm]:has-data-[slot=card-footer]:pb-0 *:[img:first-child]:rounded-t-xl *:[img:last-child]:rounded-b-xl",
+        "group/card flex flex-col gap-(--card-spacing) overflow-hidden rounded-xl border border-border/60 bg-card py-(--card-spacing) text-sm text-card-foreground shadow-[0_1px_2px_-1px_rgba(33,20,10,0.06),0_2px_8px_-2px_rgba(33,20,10,0.06)] transition-shadow [--card-spacing:--spacing(4)] has-data-[slot=card-footer]:pb-0 has-[>img:first-child]:pt-0 data-[size=sm]:[--card-spacing:--spacing(3)] data-[size=sm]:has-data-[slot=card-footer]:pb-0 *:[img:first-child]:rounded-t-xl *:[img:last-child]:rounded-b-xl",
         className
       )}
       {...props}