Performance chart under positions; remove obsolete files

- PerfChart moves into the left column under Open Positions
  (half-width), balancing the radar column.

Cleanup:
- Design mockup pages (DesignMockups / DesignHorizon / DesignOrbit)
  and their routes removed - the redesign has shipped; the mockups
  live on in git history. Main bundle shrinks ~97 kB and the
  chunk-size warning goes away.
- frontend/tsconfig.tsbuildinfo untracked and gitignored (incremental
  build artifact that churned in every commit).
- Dead npm test / test:watch scripts removed - vitest was never a
  dependency; CI already skips the step via its vitest guard.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/pages/DashboardPage.tsx

@@ -480,9 +480,12 @@ export default function DashboardPage() {
         </div>
       )}
 
-      {/* Open positions | Radar — side by side, half width each */}
+      {/* Open positions + performance | Radar — side by side, half width each */}
       <div className="grid items-start gap-8 xl:grid-cols-2">
-        <OpenTradesPanel />
+        <div className="space-y-8">
+          <OpenTradesPanel />
+          <PerfChart />
+        </div>
 
         <div>
           <Section title="Radar" hint="ranked by strategy score · select a row to focus it">
@@ -572,9 +575,6 @@ export default function DashboardPage() {
           </Section>
         </div>
       </div>
-
-      {/* Performance — the paper book vs the same dollars in SPY */}
-      <PerfChart />
     </div>
   );
 }