fix: mock hardwareConcurrency in observatory performance tests for CI consistency

CI runners have 2 cores, triggering lowQuality=true (hardwareConcurrency<=4).
This changes DPR from [1,1.2] to [1,1.1] and disables VFX pools.
Mock to 8 cores for consistent test behavior.

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

Author: bb-connor

apps/workbench/src/features/observatory/__tests__/observatory-world-canvas.performance.test.tsx

@@ -308,6 +308,8 @@ const baseProps = {
 describe("ObservatoryWorldCanvas performance flags", () => {
   beforeEach(() => {
     vi.spyOn(console, "error").mockImplementation(() => {});
+    // Ensure consistent hardware profile across local (high-core) and CI (low-core) environments
+    Object.defineProperty(navigator, "hardwareConcurrency", { configurable: true, value: 8 });
     fiberMock.canvasProps.length = 0;
     fiberMock.regress.mockReset();
     dreiMock.performanceMonitorProps.length = 0;