feat: add generic file conversion sdk example

sdk/go/examples/file-conversion/main_test.go

@@ -0,0 +1,25 @@
+package main
+
+import "testing"
+
+func TestConvertCSV(t *testing.T) {
+	out, err := convert(conversionInput{FileName: "records.csv", Content: "name,amount\nalpha,2\nbeta,3\n", TargetFormat: "json"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if out.FileName != "records.json" || out.Format != "json" || out.Rows != 2 || out.Content != `[{"amount":"2","name":"alpha"},{"amount":"3","name":"beta"}]` {
+		t.Fatalf("unexpected output: %+v", out)
+	}
+}
+
+func TestConvertRejectsMalformedCSV(t *testing.T) {
+	for _, in := range []conversionInput{
+		{FileName: "records.csv", Content: "name,amount\nalpha\n", TargetFormat: "json"},
+		{FileName: "records.csv", Content: "name,name\nalpha,beta\n", TargetFormat: "json"},
+		{FileName: "records.csv", Content: "name,amount\nalpha,2\n", TargetFormat: "xml"},
+	} {
+		if _, err := convert(in); err == nil {
+			t.Fatalf("malformed input accepted: %+v", in)
+		}
+	}
+}