perf: optimize app startup and background lifecycles

tests/unit/gpu-fallback.test.ts

@@ -0,0 +1,55 @@
+import { mkdirSync, mkdtempSync, readFileSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, describe, expect, it } from 'vitest';
+import {
+  GPU_CRASH_THRESHOLD,
+  GPU_CRASH_WINDOW_MS,
+  readGpuFallbackState,
+  recordGpuCrash,
+  shouldUseSoftwareRendering,
+} from '../../electron/main/gpu-fallback';
+
+const temporaryDirectories: string[] = [];
+
+afterEach(() => {
+  for (const directory of temporaryDirectories.splice(0)) {
+    rmSync(directory, { recursive: true, force: true });
+  }
+});
+
+describe('GPU fallback policy', () => {
+  it('enables software rendering only after repeated recent GPU failures', () => {
+    const now = 1_000_000;
+    expect(shouldUseSoftwareRendering({ state: null, now })).toBe(false);
+    expect(shouldUseSoftwareRendering({
+      state: { crashCount: GPU_CRASH_THRESHOLD, lastCrashAt: now, reason: 'crashed:1' },
+      now,
+    })).toBe(true);
+    expect(shouldUseSoftwareRendering({
+      state: {
+        crashCount: GPU_CRASH_THRESHOLD,
+        lastCrashAt: now - GPU_CRASH_WINDOW_MS - 1,
+        reason: 'crashed:1',
+      },
+      now,
+    })).toBe(false);
+    expect(shouldUseSoftwareRendering({ cliDisabled: true, now })).toBe(true);
+  });
+
+  it('persists an atomic crash counter and ignores malformed state', () => {
+    const directory = mkdtempSync(join(tmpdir(), 'makelore-gpu-'));
+    temporaryDirectories.push(directory);
+    const filePath = join(directory, 'nested', 'gpu-fallback.json');
+    const first = recordGpuCrash(filePath, 'crashed:9', 10);
+    const second = recordGpuCrash(filePath, 'oom:137', 20);
+    expect(first.crashCount).toBe(1);
+    expect(second.crashCount).toBe(2);
+    expect(readGpuFallbackState(filePath, 20)).toEqual(second);
+    expect(JSON.parse(readFileSync(filePath, 'utf8'))).toEqual(second);
+
+    mkdirSync(join(directory, 'bad'), { recursive: true });
+    const malformedPath = join(directory, 'bad', 'gpu-fallback.json');
+    expect(readGpuFallbackState(malformedPath)).toBeNull();
+  });
+});