fix: updated blog 39.0.0 to include breaking change in desktopCapturer

[Bug-Reaper]

Description of Change

Refs electron/electron#49607

PR contains big update for desktopCapturer documentation and related nuance on macOS. Notably:

Clarify macOS desktopCapture for audio has been available since macOS 13 and higher. Prior to this it was only via signed kernel extension & not supported by Chromium/Electron directly.

More recently, Chromium switched to use Apple's newer native API for audio capture.

• This new CoreAudio Tap API requires a new NSAudioCaptureUsageDescription in the App's Info.plist. Thus electron apps now require the same to use desktopCapturer properly on macOS >=14.2 where Apple introduced the API.
• Chromium implements no fallback to the older Screen & System Audio Recording permissions system if the newer API fails. Meaning electron apps that don't have the new NSAudioCaptureUsageDescription key will see desktopCapturer break on version jump v39.0.0-beta.3 to v39.0.0-beta.4. In that version jump is where we see Chromium enables the new CoreAudio Tap API by default.

In addition to doc bump for desktopCapturer this PR also adds a note about the relevant breaking change to the Electron 39.0.0 Release Blog.

A lot of the findings added in this PR came from my triage/investigation in this issue

Checklist

• This PR was not created with AI. (PRs created mainly with AI will be closed. They waste our team's time. We ban repeat offenders.)

[nikwen]

Thank you so much for your work on this!

Could you please add "Refs electron/electron#49607" at the beginning of the PR? That makes it easier for maintainers to find the related issue quickly.

[Bug-Reaper]

Great feedback @nikwen 👍 really appreciate the maintainer support on this!

Curious is there a way to preview changes made to documentation markdown in the main electron repo?

I had assumed doc changes flowed in the opposite direction so changes could be easily previewed with local instance of the doc website when being drafted/added.

[Bug-Reaper]

@nikwen per your review, sounded like we still needed to manually update the 39.0.0 release blog here? Or did we want to close this PR?

Other relevant docs changes have been merged in the main repo and should flow here shortly. Also personally curious how often they are copied over?

Thanks again for your awesome support here in the follow up to electron/electron#49607

Cheers 🥂

[nikwen]

Thank you very much!

Yes, we should update the blog post as you did.

Also personally curious how often they are copied over?

Should be pretty quick. Given that your changes aren't live on the website yet, the sync might be broken.

Curious is there a way to preview changes made to documentation markdown in the main electron repo?

Not that I know of, unfortunately.