Fix: Cannot create BrowserWindow before app is ready

[katinthehatsite]

Related to https://github.com/Automattic/dotcom-forge/issues/6878

Proposed Changes

This PR adds additional app.isReady() check to app.on( 'activate') to ensure that the app is ready before it attempts to create a browser window.

Testing Instructions

• Pull the changes from this branch locally
• Run nvm use && npm install && npm start to start the app
• Press cmd + W on macOS to close the app window but keep the app running
• Open the app again
• Confirm there are no errors in the terminal

Notes
I spent some time trying to trigger the error manually but with no luck. It seems that the steps that a user might take to trigger this error would be (since activate event is specifically designed for macOS, it would need to be tested on Mac):

• Run the application.
• Close the main window but do not quit the application. (Typically CMD + W on macOS)
• Click the application icon in the dock to reactivate it.

• I also tried simulating the activate event starting early before the app is ready by adding something like app.emit( 'activate' ) early after app initialization but that also did not trigger the error on my end;
• I am assuming that the fix would work as app.isReady() would need to be true first before the BrowserWindow is created. It seems that the activate event can possible fire ( https://github.com/Automattic/dotcom-forge/issues/6878#issuecomment-2087334306 ) before the ready event so it makes sense to add this guard in that case.

If you have any good suggestions on how to test this, let me know!

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[dcalhoun]

👋🏻 @katinthehatsite. I coincidently encountered the test failures blocking this PR. I addressed them in #80 if you have time to review. 🙇🏻 Once that merges, updating this branch with the latest trunk should fix the failing CI checks.

[katinthehatsite]

Hye @dcalhoun - thanks for the fix! I approved the PR you mentioned 👍

[sejas]

I updated trunk and that fixes the unit tests 👌 .

I also forgot to change the branch, and continued working in other issue. I pushed a commit and then reverted it 😅 , sorry for the noise.

[wojtekn]

It works fine, and the code change looks clear. Thanks for the fix.