feat: implement cmd management for targets, LUNs, and TPGTs (fixes #36)

- Fix target delete URL path mismatch (/targets/ -> /target/)
- Implement target create/delete server handlers with proper validation
- Add DeleteTarget method with force flag and mutex locking to SCSITargetService
- Implement full LU management: create/list/delete through CLI, client, and server
- Add TPGT list command to show target portal group tags
- Add unit tests for target/LU router handlers and SCSI service

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pkg/apiserver/router/lu/lu_test.go

@@ -0,0 +1,90 @@
+package lu
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gostor/gotgt/pkg/api"
+	"github.com/gostor/gotgt/pkg/scsi"
+	"golang.org/x/net/context"
+)
+
+func resetService() {
+	s := scsi.NewSCSITargetService()
+	targets, _ := s.GetTargetList()
+	for _, t := range targets {
+		s.DeleteTarget(t.Name, true)
+	}
+}
+
+func TestGetLuListEmpty(t *testing.T) {
+	resetService()
+	r := &luRouter{}
+
+	req, _ := http.NewRequest("GET", "/lu/list?target=iqn.test", nil)
+	req.ParseForm()
+	w := httptest.NewRecorder()
+
+	err := r.getLuList(context.Background(), w, req, nil)
+	if err != nil {
+		t.Fatalf("getLuList failed: %v", err)
+	}
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected status 200, got %d", w.Code)
+	}
+
+	var lus []api.LuInfo
+	if err := json.Unmarshal(w.Body.Bytes(), &lus); err != nil {
+		t.Fatalf("failed to decode response: %v", err)
+	}
+	if len(lus) != 0 {
+		t.Fatalf("expected 0 LUs for non-existent target, got %d", len(lus))
+	}
+}
+
+func TestGetLuListNoTarget(t *testing.T) {
+	r := &luRouter{}
+
+	req, _ := http.NewRequest("GET", "/lu/list", nil)
+	w := httptest.NewRecorder()
+
+	err := r.getLuList(context.Background(), w, req, nil)
+	if err == nil {
+		t.Fatal("expected error when target param is missing")
+	}
+}
+
+func TestDeleteLu(t *testing.T) {
+	resetService()
+	r := &luRouter{}
+
+	body, _ := json.Marshal(api.LuRemoveOptions{TargetName: "iqn.test", LUN: 0})
+	req, _ := http.NewRequest("DELETE", "/lu/delete", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	err := r.deleteLu(context.Background(), w, req, nil)
+	if err != nil {
+		t.Fatalf("deleteLu failed: %v", err)
+	}
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected status 204, got %d", w.Code)
+	}
+}
+
+func TestDeleteLuNoTarget(t *testing.T) {
+	r := &luRouter{}
+
+	body, _ := json.Marshal(api.LuRemoveOptions{TargetName: "", LUN: 0})
+	req, _ := http.NewRequest("DELETE", "/lu/delete", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	err := r.deleteLu(context.Background(), w, req, nil)
+	if err == nil {
+		t.Fatal("expected error when target name is empty")
+	}
+}