Prepare release v30.0.0

- drawio submodule: unchanged (no drawio_ref supplied; CI builds from drawio-dev) (c9904435fd1a6795f6cad5c3908ec89d9afb8fb1)
- Updated package.json version to 30.0.0
- Updated package-lock.json
- Electron version: 42.0.1

Automated by prepare-release workflow