refactor: reorganize models to pkg/model and add authentication module

- Move ORM models from internal/model to pkg/model organized by module (auth/k8s/registry)
- Add authentication module with login, user management handlers
- Update all import paths to use new model locations
- Add frontend auth pages (Login, UserManagement) and authStore
- Remove deprecated internal/model/model.go

internal/api/api.go

@@ -7,9 +7,10 @@ import (
 	"net"
 
 	"gitea.loveuer.com/loveuer/cluster/internal/middleware"
-	"gitea.loveuer.com/loveuer/cluster/internal/model"
+	"gitea.loveuer.com/loveuer/cluster/internal/module/auth"
 	"gitea.loveuer.com/loveuer/cluster/internal/module/k8s"
 	"gitea.loveuer.com/loveuer/cluster/internal/module/registry"
+	registry_model "gitea.loveuer.com/loveuer/cluster/pkg/model/registry"
 	"gitea.loveuer.com/loveuer/cluster/pkg/store"
 	"github.com/gofiber/fiber/v3"
 	"gorm.io/gorm"
@@ -33,10 +34,15 @@ func Init(ctx context.Context, address string, db *gorm.DB, store store.Store) (
 
 	// Ensure database migration for RegistryConfig
 	// This is done here to ensure the table exists before config APIs are called
-	if err := db.AutoMigrate(&model.RegistryConfig{}); err != nil {
+	if err := db.AutoMigrate(&registry_model.RegistryConfig{}); err != nil {
 		log.Printf("Warning: failed to migrate RegistryConfig: %v", err)
 	}
 
+	// Initialize auth module
+	if err := auth.Init(ctx, db); err != nil {
+		log.Printf("Warning: failed to initialize auth module: %v", err)
+	}
+
 	// Initialize k8s module
 	if err := k8s.Init(ctx, db, store); err != nil {
 		log.Printf("Warning: failed to initialize k8s module: %v", err)
@@ -87,6 +93,20 @@ func Init(ctx context.Context, address string, db *gorm.DB, store store.Store) (
 		k8sAPI.Delete("/service/delete", k8s.K8sServiceDelete(ctx, db, store))
 	}
 
+	// auth apis
+	{
+		authAPI := app.Group("/api/v1/auth")
+		authAPI.Post("/login", auth.Login(ctx, db))
+		authAPI.Get("/wallpaper", auth.Wallpaper(ctx))
+		authAPI.Get("/current", auth.GetCurrentUser(ctx))
+		
+		// user management
+		authAPI.Get("/user/list", auth.UserList(ctx, db))
+		authAPI.Post("/user/create", auth.UserCreate(ctx, db))
+		authAPI.Post("/user/update/:id", auth.UserUpdate(ctx, db))
+		authAPI.Delete("/user/delete/:id", auth.UserDelete(ctx, db))
+	}
+
 	ln, err = net.Listen("tcp", address)
 	if err != nil {
 		return fn, fmt.Errorf("failed to listen on %s: %w", address, err)