feat: Allow user-agent based conditions (#1821)

* Closes #1819

tests/utils/companion.test.ts

@@ -0,0 +1,20 @@
+import { describe, expect, it } from 'vitest';
+import { isCompanionApp } from '../../src/utils/companion';
+
+describe('isCompanionApp', () => {
+  it('should return true for userAgent starting with "Home Assistant/"', () => {
+    expect(isCompanionApp('Home Assistant/1.0')).toBe(true);
+  });
+
+  it('should return true for userAgent starting with "HomeAssistant/"', () => {
+    expect(isCompanionApp('HomeAssistant/1.0')).toBe(true);
+  });
+
+  it('should return false for userAgent not starting with "Home Assistant/" or "HomeAssistant/"', () => {
+    expect(isCompanionApp('Mozilla/5.0')).toBe(false);
+  });
+
+  it('should return false for an empty userAgent', () => {
+    expect(isCompanionApp('')).toBe(false);
+  });
+});