fix(registry): clone model snapshots and invalidate available-model cache

internal/registry/model_registry_cache_test.go

@@ -0,0 +1,54 @@
+package registry
+
+import "testing"
+
+func TestGetAvailableModelsReturnsClonedSnapshots(t *testing.T) {
+	r := newTestModelRegistry()
+	r.RegisterClient("client-1", "OpenAI", []*ModelInfo{{ID: "m1", OwnedBy: "team-a", DisplayName: "Model One"}})
+
+	first := r.GetAvailableModels("openai")
+	if len(first) != 1 {
+		t.Fatalf("expected 1 model, got %d", len(first))
+	}
+	first[0]["id"] = "mutated"
+	first[0]["display_name"] = "Mutated"
+
+	second := r.GetAvailableModels("openai")
+	if got := second[0]["id"]; got != "m1" {
+		t.Fatalf("expected cached snapshot to stay isolated, got id %v", got)
+	}
+	if got := second[0]["display_name"]; got != "Model One" {
+		t.Fatalf("expected cached snapshot to stay isolated, got display_name %v", got)
+	}
+}
+
+func TestGetAvailableModelsInvalidatesCacheOnRegistryChanges(t *testing.T) {
+	r := newTestModelRegistry()
+	r.RegisterClient("client-1", "OpenAI", []*ModelInfo{{ID: "m1", OwnedBy: "team-a", DisplayName: "Model One"}})
+
+	models := r.GetAvailableModels("openai")
+	if len(models) != 1 {
+		t.Fatalf("expected 1 model, got %d", len(models))
+	}
+	if got := models[0]["display_name"]; got != "Model One" {
+		t.Fatalf("expected initial display_name Model One, got %v", got)
+	}
+
+	r.RegisterClient("client-1", "OpenAI", []*ModelInfo{{ID: "m1", OwnedBy: "team-a", DisplayName: "Model One Updated"}})
+	models = r.GetAvailableModels("openai")
+	if got := models[0]["display_name"]; got != "Model One Updated" {
+		t.Fatalf("expected updated display_name after cache invalidation, got %v", got)
+	}
+
+	r.SuspendClientModel("client-1", "m1", "manual")
+	models = r.GetAvailableModels("openai")
+	if len(models) != 0 {
+		t.Fatalf("expected no available models after suspension, got %d", len(models))
+	}
+
+	r.ResumeClientModel("client-1", "m1")
+	models = r.GetAvailableModels("openai")
+	if len(models) != 1 {
+		t.Fatalf("expected model to reappear after resume, got %d", len(models))
+	}
+}