fix(companion): resolve fixtures path correctly in Electron runtime

tests/integration/companion/di-container.test.ts

@@ -0,0 +1,66 @@
+import { describe, it, expect } from 'vitest';
+import * as path from 'path';
+import { resolveFixturesPath } from '@/apps/companion/main/di-container';
+
+describe('DIContainer path resolution', () => {
+  describe('resolveFixturesPath', () => {
+    it('should resolve fixtures path to monorepo root when app path is apps/companion/dist/main', () => {
+      // Given: The app path as it would be in Electron runtime (apps/companion/dist/main)
+      const mockAppPath = '/Users/test/Projects/gridpilot/apps/companion/dist/main';
+      const relativePath = './resources/iracing-hosted-sessions';
+
+      // When: Resolving the fixtures path
+      const resolved = resolveFixturesPath(relativePath, mockAppPath);
+
+      // Then: Should resolve to monorepo root (4 levels up from apps/companion/dist/main)
+      // Level 0: apps/companion/dist/main (app.getAppPath())
+      // Level 1: apps/companion/dist (../)
+      // Level 2: apps/companion (../../)
+      // Level 3: apps (../../../)
+      // Level 4: gridpilot (monorepo root) (../../../../) ← CORRECT
+      const expectedPath = '/Users/test/Projects/gridpilot/resources/iracing-hosted-sessions';
+      expect(resolved).toBe(expectedPath);
+    });
+
+    it('should return absolute paths unchanged', () => {
+      // Given: An absolute path
+      const absolutePath = '/some/absolute/path/to/fixtures';
+      const mockAppPath = '/Users/test/Projects/gridpilot/apps/companion/dist/main';
+
+      // When: Resolving an absolute path
+      const resolved = resolveFixturesPath(absolutePath, mockAppPath);
+
+      // Then: Should return the absolute path unchanged
+      expect(resolved).toBe(absolutePath);
+    });
+
+    it('should navigate exactly 4 levels up from app path', () => {
+      // Given: A path that demonstrates the 4-level navigation
+      const mockAppPath = '/level4/level3/level2/level1';
+      const relativePath = './target';
+
+      // When: Resolving the fixtures path
+      const resolved = resolveFixturesPath(relativePath, mockAppPath);
+
+      // Then: Should resolve to the path 4 levels up (root /)
+      // Level 0: /level4/level3/level2/level1 (appPath)
+      // Level 1: /level4/level3/level2 (../)
+      // Level 2: /level4/level3 (../../)
+      // Level 3: /level4 (../../../)
+      // Level 4: / (../../../../) ← monorepo root equivalent
+      expect(resolved).toBe('/target');
+    });
+
+    it('should work with different relative path formats', () => {
+      // Given: Various relative path formats
+      const mockAppPath = '/Users/test/Projects/gridpilot/apps/companion/dist/main';
+
+      // When/Then: Different relative formats should all work
+      expect(resolveFixturesPath('resources/fixtures', mockAppPath))
+        .toBe('/Users/test/Projects/gridpilot/resources/fixtures');
+      
+      expect(resolveFixturesPath('./resources/fixtures', mockAppPath))
+        .toBe('/Users/test/Projects/gridpilot/resources/fixtures');
+    });
+  });
+});