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/target/target_test.go

@@ -0,0 +1,124 @@
+package target
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gostor/gotgt/pkg/api"
+	"github.com/gostor/gotgt/pkg/scsi"
+	_ "github.com/gostor/gotgt/pkg/scsi/backingstore"
+	"golang.org/x/net/context"
+)
+
+func resetService() *scsi.SCSITargetService {
+	s := scsi.NewSCSITargetService()
+	// Clear targets for test isolation
+	targets, _ := s.GetTargetList()
+	for _, t := range targets {
+		s.DeleteTarget(t.Name, true)
+	}
+	return s
+}
+
+func TestPostTargetCreate(t *testing.T) {
+	resetService()
+	r := &targetRouter{}
+
+	body, _ := json.Marshal(api.TargetCreateRequest{Name: "iqn.2016-09.com.gotgt:test"})
+	req, _ := http.NewRequest("POST", "/target/create", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	err := r.postTargetCreate(context.Background(), w, req, nil)
+	if err != nil {
+		t.Fatalf("postTargetCreate failed: %v", err)
+	}
+	if w.Code != http.StatusCreated {
+		t.Fatalf("expected status 201, got %d", w.Code)
+	}
+
+	var target api.SCSITarget
+	if err := json.Unmarshal(w.Body.Bytes(), &target); err != nil {
+		t.Fatalf("failed to decode response: %v", err)
+	}
+	if target.Name != "iqn.2016-09.com.gotgt:test" {
+		t.Fatalf("expected target name iqn.2016-09.com.gotgt:test, got %s", target.Name)
+	}
+}
+
+func TestPostTargetCreateEmptyName(t *testing.T) {
+	resetService()
+	r := &targetRouter{}
+
+	body, _ := json.Marshal(api.TargetCreateRequest{Name: ""})
+	req, _ := http.NewRequest("POST", "/target/create", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	err := r.postTargetCreate(context.Background(), w, req, nil)
+	if err == nil {
+		t.Fatal("expected error for empty target name")
+	}
+}
+
+func TestDeleteTarget(t *testing.T) {
+	s := resetService()
+	r := &targetRouter{}
+
+	s.NewSCSITarget(0, "iscsi", "iqn.2016-09.com.gotgt:to_delete")
+
+	req, _ := http.NewRequest("DELETE", "/target/iqn.2016-09.com.gotgt:to_delete", nil)
+	w := httptest.NewRecorder()
+
+	vars := map[string]string{"name": "iqn.2016-09.com.gotgt:to_delete"}
+	err := r.deleteTarget(context.Background(), w, req, vars)
+	if err != nil {
+		t.Fatalf("deleteTarget failed: %v", err)
+	}
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected status 204, got %d", w.Code)
+	}
+}
+
+func TestDeleteTargetNotFound(t *testing.T) {
+	resetService()
+	r := &targetRouter{}
+
+	req, _ := http.NewRequest("DELETE", "/target/nonexistent", nil)
+	w := httptest.NewRecorder()
+
+	vars := map[string]string{"name": "nonexistent"}
+	err := r.deleteTarget(context.Background(), w, req, vars)
+	if err == nil {
+		t.Fatal("expected error deleting nonexistent target")
+	}
+}
+
+func TestGetTargetList(t *testing.T) {
+	s := resetService()
+	r := &targetRouter{}
+
+	s.NewSCSITarget(0, "iscsi", "iqn.2016-09.com.gotgt:list_test")
+
+	req, _ := http.NewRequest("GET", "/target/list", nil)
+	w := httptest.NewRecorder()
+
+	err := r.getTargetList(context.Background(), w, req, nil)
+	if err != nil {
+		t.Fatalf("getTargetList failed: %v", err)
+	}
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected status 200, got %d", w.Code)
+	}
+
+	var targets []*api.SCSITarget
+	if err := json.Unmarshal(w.Body.Bytes(), &targets); err != nil {
+		t.Fatalf("failed to decode response: %v", err)
+	}
+	if len(targets) == 0 {
+		t.Fatal("expected at least one target")
+	}
+}