Versioning scheme: MAJOR.MINOR.PATCH where MAJOR matches the wire
protocol version (no cross-major compat), MINOR is the main change
indicator, PATCH generally unused.
- gatunad: Cargo.toml version 2.0.0 (clap --version picks it up)
- gatuna: csproj Version 2.0.0, shown in form title + tray tooltip
- app.manifest: assemblyIdentity version 2.0.0.0
- Frame version rejection already in place (both sides reject != 2)
- README: document versioning scheme