fix(hold-history): auto-scale summary card font to prevent overflow

Use CSS container queries to dynamically size summary values based on
card width, preventing large QTY numbers from overflowing the 7-column
card grid.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/hold-history/style.css

@@ -135,6 +135,14 @@
   grid-template-columns: repeat(7, minmax(0, 1fr));
 }
 
+.hold-history-summary-row .summary-card {
+  container-type: inline-size;
+}
+
+.hold-history-summary-row .summary-value {
+  font-size: clamp(14px, 12cqi, 28px);
+}
+
 .summary-card {
   border: 1px solid var(--border);
 }