test: suppress console.log output in eventStream test

Added console.log mock in eventStream.test.js to suppress the 'EventStream error' message that was appearing during test execution. This improves test output cleanliness by preventing the expected error logging from the eventStream error handling code from cluttering the test console output.

The mock follows the existing pattern used in the codebase for suppressing console output during tests and only affects the test environment, preserving the original logging functionality in production code.

ui/src/eventStream.test.js

@@ -32,6 +32,8 @@ describe('startEventStream', () => {
     localStorage.setItem('is-authenticated', 'true')
     localStorage.setItem('token', 'abc')
     config.devNewEventStream = true
+    // Mock console.log to suppress output during tests
+    vi.spyOn(console, 'log').mockImplementation(() => {})
   })
 
   afterEach(() => {