Implement controlled app launch (T-401)

app-modern/platform/windows/platform_stub.go

@@ -2,7 +2,11 @@
 
 package windows
 
-import "runtime"
+import (
+	"runtime"
+
+	"softbox.local/core/application/launch"
+)
 
 type platformStub struct{}
 
@@ -17,3 +21,15 @@ func (platformStub) OS() string {
 func (platformStub) Edition() Edition {
 	return EditionModern
 }
+
+func (platformStub) IsCompatible(string) (bool, error) {
+	return false, ErrUnsupported
+}
+
+func (platformStub) IsRunning(string, string) (bool, error) {
+	return false, ErrUnsupported
+}
+
+func (platformStub) Start(launch.Command) (int, error) {
+	return 0, ErrUnsupported
+}