feat: simplify SOP to immediate-effect configuration

internal/knowledge/graph_test.go

@@ -0,0 +1,13 @@
+package knowledge
+
+import "testing"
+
+func TestNormalizeGraphInputSupportsMultipleDiseases(t *testing.T) {
+	items, relations, err := normalizeGraphInput(GraphInput{Symptoms: []SymptomInput{{Key: "poor_appetite", Name: "食欲下降", Diseases: []GraphItemInput{{Key: "gi", Name: "肠胃不适"}, {Key: "dental", Name: "口腔问题"}}}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(items) != 3 || len(relations) != 2 {
+		t.Fatalf("items=%d relations=%d", len(items), len(relations))
+	}
+}