fix(fe): fix ModelList (models-master) scroll on first load - apply height propagation standard

Problem: .master-list had hardcoded height: calc(100vh - 210px), causing scroll on first load

Changes:
  • .master-list: calc(100vh - 210px) → flex: 1; min-height: 0;
  • .items: Added missing min-height: 0; (required for flex children)

Result: Single-screen principle restored (no page-level scroll, height fills viewport)

This aligns with AGENTS.md Height Propagation Chain standard.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

frontend/src/features/models/pages/ModelList.vue

@@ -376,7 +376,8 @@ h3 {
   border-radius: var(--ks-radius-sm);
   overflow: hidden;
   background: var(--ks-color-surface);
-  height: calc(100vh - 210px);
+  flex: 1;
+  min-height: 0;
   display: flex;
   flex-direction: column;
 }
@@ -397,6 +398,7 @@ h3 {
   gap: var(--ks-space-2);
   padding: var(--ks-space-2);
   flex: 1;
+  min-height: 0;
   overflow-y: auto;
 }