feat: add Go SDK package (REST client + VL1 agent + TAP device)

sdk/tap_stub.go

@@ -0,0 +1,26 @@
+//go:build !linux
+
+package sdk
+
+import "fmt"
+
+type tapInterface struct {
+	Name string
+	MTU  int
+}
+
+func openTap(name string, mtu int) (*tapInterface, error) {
+	return nil, fmt.Errorf("TAP device requires Linux")
+}
+
+func (ti *tapInterface) Read(buf []byte) (int, error) {
+	return 0, fmt.Errorf("not supported")
+}
+
+func (ti *tapInterface) Write(buf []byte) error {
+	return fmt.Errorf("not supported")
+}
+
+func (ti *tapInterface) Close() error {
+	return nil
+}