Update Electron to version 42.0.1

[sergiou87]

Summary

This PR updates Electron from v40.1.0 to v42.0.1 (skipping v41).
Node.js is also updated from v24.11.1 to v24.15.0 to match the version bundled with Electron 42.

Electron 42 ships with Chromium 148 and V8 14.8.

Breaking Changes

Electron 41

• Behavior Changed: PDFs no longer create a separate WebContents.
• Behavior Changed: Updated cookie change cause in the cookie changed event.
• Deprecated: showHiddenFiles in dialogs on Linux (still honored on macOS and Windows).

Electron 42

• Behavior Changed: macOS notifications now use the UNNotification API. The new API requires the application to be code-signed in order for notifications to be displayed; an unsigned app will emit a failed event on the Notification object instead. GitHub Desktop is not affected as we use our own library desktop-notifications.
• Behavior Changed: Offscreen rendering now uses 1.0 as the default device scale factor (previously the primary display's scale factor). Not used by GitHub Desktop.
• Behavior Changed: electron no longer downloads itself via the postinstall script — the download now happens lazily on first require. Worth keeping an eye on CI / first-run behavior.
• Removed: quotas object from Session.clearStorageData(options). Not used by GitHub Desktop.
• Deprecated: Passing only an array hslShift to nativeImage.createFromNamedImage().

⚠️ OS Compatibility Changes

No changes — Electron 41 and 42 do not raise the minimum supported OS versions:

• macOS: still macOS 12 (Monterey) or later (last raised in Electron 38).
• Windows: still Windows 10 1809 or later.

References

• Electron v42.0.1 Release Notes
• Electron v42.0.0 Release Notes
• Electron v41.0.0 Release Notes
• Electron Breaking Changes

[Copilot]

Pull request overview

This PR bumps the app’s Electron dependency from 40.1.0 to 42.0.1 (skipping 41) and updates the repository’s Node.js version pins to match the Node version bundled with Electron 42, ensuring local development and CI use the same runtime baseline.

Changes:

• Update Electron to 42.0.1 across dependency/config pins.
• Update Node.js from 24.11.1 to 24.15.0 in toolchain/version files and CI.
• Refresh yarn.lock to reflect the Electron update and its transitive dependency changes (e.g., @electron/get@5).

Show a summary per file

File	Description
yarn.lock	Locks Electron 42.0.1 and updates transitive deps (e.g., @electron/get@5, undici).
script/validate-electron-version.ts	Updates the validated Electron version for release channels (but currently only for beta).
package.json	Bumps the Electron devDependency to 42.0.1.
app/.npmrc	Updates the Electron headers target used for native module builds to 42.0.1.
.tool-versions	Updates the pinned Node.js version to 24.15.0.
.nvmrc	Updates the pinned Node.js version to v24.15.0.
.node-version	Updates the pinned Node.js version to 24.15.0.
.github/workflows/ci.yml	Updates CI’s Node.js version to 24.15.0.

Copilot's findings

• Files reviewed: 7/8 changed files
• Comments generated: 1