Refresh Electron prebuild target and demo apps

[minggangw]

The prebuild:electron script was still pinned to electron@23.0.0, an EOL release from Dec 2022 that bundles Node 18.12. Bump it to electron@34.0.0, the most recent line whose bundled Node (20.18.1) matches the major version of our engines.node >= 20.20.2 floor.

The four electron_demo/* apps were pinned to ^40.1.0, which goes EOL on Jun 30, 2026. Bump them to ^41.0.0 (supported through Aug 25, 2026) so demos stay on a maintained, security-patched Electron line ahead of the Lyrical GA window.

N-API ABI stability means binaries built against Electron 34 continue to load cleanly in 41+, so the prebuild-target / demo-target split is intentional and safe.

Fix: #1458

[Copilot]

Pull request overview

Updates Electron versions used for building Electron-specific prebuilt binaries and for the Electron demo applications, aligning the project with maintained Electron release lines ahead of the ROS 2 Lyrical window.

Changes:

• Bump the prebuild:electron target from electron@23.0.0 to electron@34.0.0.
• Update all electron_demo/* apps from electron@^40.1.0 to electron@^41.0.0.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
package.json	Updates the Electron runtime target used when generating Electron prebuilds.
electron_demo/turtle_tf2/package.json	Bumps demo app Electron dependency to a newer supported major line.
electron_demo/topics/package.json	Bumps demo app Electron dependency to a newer supported major line.
electron_demo/manipulator/package.json	Bumps demo app Electron dependency to a newer supported major line.
electron_demo/car/package.json	Bumps demo app Electron dependency to a newer supported major line.

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[coveralls]

coverage: 85.864%. remained the same — minggangw:fix-1458-5 into RobotWebTools:develop