S06-S08: Python spec, Go in-process leaf, tests and Forgejo CI

go/internal/leaf/leaf_test.go

@@ -0,0 +1,14 @@
+package leaf
+
+import "testing"
+
+func TestStartInProcess(t *testing.T) {
+	n, err := Start("")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer n.Shutdown()
+	if n.Addr() == "" {
+		t.Fatal("empty addr")
+	}
+}