feat: replace text labels with icons in runtime cards

Use Activity, Cpu, and HeartPulse icons instead of "tps", "cpu", and
"ago" text in compact and expanded app cards. Bump design-system to
v0.1.55 for sidebar footer alignment fix.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/utils/format-utils.ts

@@ -24,16 +24,17 @@ export function statusLabel(s: string): string {
   return s.charAt(0).toUpperCase() + s.slice(1).toLowerCase();
 }
 
-export function timeAgo(iso?: string): string {
+export function timeAgo(iso?: string, short = false): string {
   if (!iso) return '\u2014';
   const diff = Date.now() - new Date(iso).getTime();
   const secs = Math.floor(diff / 1000);
-  if (secs < 60) return `${secs}s ago`;
+  const suffix = short ? '' : ' ago';
+  if (secs < 60) return `${secs}s${suffix}`;
   const mins = Math.floor(secs / 60);
-  if (mins < 60) return `${mins}m ago`;
+  if (mins < 60) return `${mins}m${suffix}`;
   const hours = Math.floor(mins / 60);
-  if (hours < 24) return `${hours}h ago`;
-  return `${Math.floor(hours / 24)}d ago`;
+  if (hours < 24) return `${hours}h${suffix}`;
+  return `${Math.floor(hours / 24)}d${suffix}`;
 }
 
 export function formatMetric(value: number, unit: string, decimals = 1): string {