Add protocol selection to Claude and Codex provider forms referencing CCSwitch

internal/config/config_test.go

@@ -337,3 +337,48 @@ func TestSetGatewayValidation(t *testing.T) {
 		t.Error("unknown language accepted")
 	}
 }
+
+func TestProviderProtocol(t *testing.T) {
+	t.Setenv("CROSSRELAY_HOME", t.TempDir())
+	store, err := Load()
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+
+	// 1. Default protocol when omitted should be openai_chat.
+	p1, err := store.AddProvider("Claude-Default", "", "https://api.example.com/v1", "sk-1", Models{}, TargetClaude)
+	if err != nil {
+		t.Fatalf("AddProvider: %v", err)
+	}
+	if p1.Protocol != ProtocolOpenAIChat || p1.APIFormat != ProtocolOpenAIChat {
+		t.Errorf("expected default protocol %q, got protocol=%q, api_format=%q", ProtocolOpenAIChat, p1.Protocol, p1.APIFormat)
+	}
+
+	// 2. Explicit protocol should be saved.
+	p2, err := store.AddProvider("Claude-Anthropic", "", "https://api.anthropic.com/v1", "sk-2", Models{}, TargetClaude, ProtocolAnthropic)
+	if err != nil {
+		t.Fatalf("AddProvider with protocol: %v", err)
+	}
+	if p2.Protocol != ProtocolAnthropic {
+		t.Errorf("expected protocol %q, got %q", ProtocolAnthropic, p2.Protocol)
+	}
+
+	// 3. Update protocol.
+	updated, err := store.UpdateProvider(p2.ID, "Claude-Anthropic-Updated", "", "https://api.anthropic.com/v1", "sk-2", Models{}, TargetClaude, ProtocolOpenAIResponses)
+	if err != nil {
+		t.Fatalf("UpdateProvider with protocol: %v", err)
+	}
+	if updated.Protocol != ProtocolOpenAIResponses {
+		t.Errorf("expected updated protocol %q, got %q", ProtocolOpenAIResponses, updated.Protocol)
+	}
+
+	// 4. Persistence round-trip.
+	reloaded, err := Load()
+	if err != nil {
+		t.Fatalf("Load reloaded: %v", err)
+	}
+	found := reloaded.FindProvider(p2.ID)
+	if found == nil || found.Protocol != ProtocolOpenAIResponses {
+		t.Errorf("expected persisted protocol %q, got %+v", ProtocolOpenAIResponses, found)
+	}
+}