`make build`/`make install` now compile the C `clide` client by default
(clide-cli is a prereq of both), and `make install` places that binary at
$(INSTALL_DIR)/clide on Linux and macOS instead of symlinking the Flutter
GUI runner. The GUI still launches via its desktop entry / clide.app.
macOS install now delivers the CLI too; macOS uninstall removes it.
Adds a regression test asserting clideVersion (build_info.g.dart) stays
equal to pubspec.yaml version, so an agent keying off `clide version` is
never misled.
Closes T-210, T-211, T-213 (under T-209 / T-208 "Give Claude hands").
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>