chore: update DS to v0.1.38, enforce 12px font size floor

Update @cameleer/design-system to v0.1.38 (12px minimum font size).
Replace all 10px and 11px font sizes with 12px across 25 CSS modules
and 5 TSX inline styles to match the new DS floor.

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

ui/src/pages/Exchanges/ExchangeHeader.module.css

@@ -117,7 +117,7 @@
 
 .chainTotal {
   font-family: var(--font-mono);
-  font-size: 10px;
+  font-size: 12px;
   font-weight: 600;
   color: var(--text-secondary);
   margin-left: auto;
@@ -131,7 +131,7 @@
 
 .chainArrow {
   color: var(--text-faint, var(--text-muted));
-  font-size: 10px;
+  font-size: 12px;
   margin: 0 4px;
   flex-shrink: 0;
 }
@@ -143,7 +143,7 @@
   padding: 3px 8px;
   border-radius: var(--radius-sm);
   border: 1px solid var(--border-subtle);
-  font-size: 10px;
+  font-size: 12px;
   font-family: var(--font-mono);
   cursor: pointer;
   background: var(--bg-surface);
@@ -197,6 +197,6 @@
 
 .chainNone {
   color: var(--text-muted);
-  font-size: 11px;
+  font-size: 12px;
   font-style: italic;
 }

ui/src/pages/Exchanges/RouteControlBar.module.css

@@ -37,7 +37,7 @@
   border: none;
   background: none;
   font: inherit;
-  font-size: 11px;
+  font-size: 12px;
   font-weight: 500;
   color: var(--text-secondary);
   cursor: pointer;