test(ws,browser): add test suites for ws and browser packages (#22)

- Add ws/server_test.go: WebSocket connection, namespace filtering, non-upgrade rejection, SetUpgrader
- Add ws/namespaces_test.go: NamespacesHandler response format and content
- Add browser/browser_test.go: template rendering, ws URL construction, trailing slash handling
- Fix goimports whitespace in ws/server.go

ws/namespaces_test.go

@@ -0,0 +1,62 @@
+package ws
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	logger "github.com/taigrr/log-socket/v2/log"
+)
+
+func TestNamespacesHandler(t *testing.T) {
+	// Log to a known namespace to ensure it appears
+	nsLogger := logger.NewLogger("ns-handler-test")
+	nsLogger.Info("register namespace")
+
+	req := httptest.NewRequest(http.MethodGet, "/api/namespaces", nil)
+	w := httptest.NewRecorder()
+	NamespacesHandler(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("status = %d, want 200", w.Code)
+	}
+
+	ct := w.Header().Get("Content-Type")
+	if ct != "application/json" {
+		t.Errorf("Content-Type = %q, want application/json", ct)
+	}
+
+	var result struct {
+		Namespaces []string `json:"namespaces"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &result); err != nil {
+		t.Fatalf("failed to unmarshal response: %v", err)
+	}
+
+	found := false
+	for _, ns := range result.Namespaces {
+		if ns == "ns-handler-test" {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Errorf("namespace 'ns-handler-test' not found in %v", result.Namespaces)
+	}
+}
+
+func TestNamespacesHandler_ResponseFormat(t *testing.T) {
+	req := httptest.NewRequest(http.MethodGet, "/api/namespaces", nil)
+	w := httptest.NewRecorder()
+	NamespacesHandler(w, req)
+
+	var result map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &result); err != nil {
+		t.Fatalf("response is not valid JSON: %v", err)
+	}
+
+	if _, ok := result["namespaces"]; !ok {
+		t.Error("response missing 'namespaces' key")
+	}
+}