feat(electron-updater): allow overriding AppUpdater.isStagingMatch

[Lemonexe]

Alternative implementation for #9016

Add get/set/protected isUserWithinRollout interface to AppUpdater class, similarly to how it is implemented for isUpdateSupported so that you can override the default calculation of staging percentage.
The user will be offerred an update if the other necessary conditions are met, but they would otherwise be below the rollout threshold.

Usecase

staging rollout is observed when automatically querying for updates in background, but we also have a manual "Check for updates" button in Settings. This will allow the manual check to always offer you the latest version.

[changeset-bot]

🦋 Changeset detected

Latest commit: f704bf6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
electron-updater	Patch

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[mmaietta]

This is clean! Thank you for the contribution

Quick request, can you generate a changeset file for this using pnpm generate-changeset so that it's picked up by the CD pipeline? Might want to run pnpm generate-all as well to verify prettier.

[Lemonexe]

@mmaietta Done. I ran lint, lint-deps, generate-changeset and generate-all ✔️

The last one generated a diff in app-build-lib/scheme.json (differs only in text). Though I did not commit that, to avoid mixing multiple packages in one commit..