standardize design to s/w standard - fix non-standard color usage

- replace hardcoded green/red/blue colors with standard shadcn semantic colors
- use text-primary, text-secondary-foreground, text-muted-foreground instead of text-green-600/blue-600
- replace colored backgrounds with bg-secondary, bg-muted, bg-primary/5
- maintain proper contrast and accessibility with semantic color tokens
- ensure consistent black/white theme across all components

src/client/features/legislation/components/legislation-detail.tsx

@@ -51,7 +51,7 @@ export function LegislationDetail({ legislationId }: LegislationDetailProps) {
 					{legislation.title}
 				</h1>
 				{legislation.beratungsstand && (
-					<span className="inline-block mt-2 text-xs px-2 py-1 rounded-full bg-blue-100 text-blue-800">
+					<span className="inline-block mt-2 text-xs px-2 py-1 rounded-full bg-secondary text-secondary-foreground">
 						{legislation.beratungsstand}
 					</span>
 				)}
@@ -78,7 +78,7 @@ export function LegislationDetail({ legislationId }: LegislationDetailProps) {
 					<button
 						type="button"
 						onClick={() => setShowFullText(!showFullText)}
-						className="text-sm text-blue-600 hover:underline"
+						className="text-sm text-primary hover:underline"
 					>
 						{showFullText ? "Volltext ausblenden" : "Volltext anzeigen"}
 					</button>