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/AgentInstance/AgentInstance.module.css

@@ -35,7 +35,7 @@
 
 .scopeSep {
   color: var(--text-muted);
-  font-size: 10px;
+  font-size: 12px;
 }
 
 .scopeCurrent {
@@ -113,7 +113,7 @@
 }
 
 .chartMeta {
-  font-size: 11px;
+  font-size: 12px;
   color: var(--text-muted);
   font-family: var(--font-mono);
 }
@@ -222,7 +222,7 @@
   background: none;
   border: none;
   color: var(--text-muted);
-  font-size: 11px;
+  font-size: 12px;
   cursor: pointer;
   padding: 2px 6px;
   white-space: nowrap;