fix: user-did-{resign|become}-active events on macOS

[codebytere]

Description of Change

Closes #41497.

Fixes an issue where user-did-{resign|become}-active were not emitted properly on macOS.

This was happening because per docs the notification object is the shared NSWorkspace instance - we need to add an observer to [[NSWorkspace sharedWorkspace] notificationCenter] and not [NSDistributedNotificationCenter defaultCenter].

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.

Release Notes

Notes: Fixed an issue where user-did-{resign|become}-active were not emitted properly on macOS.

[brondibur]

Hi @codebytere
Thanks for jumping on this super quickly. I noticed the 26-x-y labels are missing from both the issue and the PR.
On https://www.electronjs.org/docs/latest/tutorial/electron-timelines I see a green checkmark for Electron v26, but EOL date is Feb 20, 2024.
Does this mean the fix won't be available for Electron v26? What about Electron v27?

[codebytere]

@brondibur unfortunately no - we maintain four release lines at any given time, with the oldest being primarily security-related fixes. I've opened a PR to correct the doc.

[release-clerk]

Release Notes Persisted

Fixed an issue where user-did-{resign|become}-active were not emitted properly on macOS.

[trop]

I have automatically backported this PR to "28-x-y", please check out #41526

[trop]

I have automatically backported this PR to "29-x-y", please check out #41527

[trop]

I have automatically backported this PR to "30-x-y", please check out #41528