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/module/auth/handler.current.go

@@ -0,0 +1,42 @@
+package auth
+
+import (
+	"context"
+
+	"gitea.loveuer.com/loveuer/cluster/pkg/resp"
+	"github.com/gofiber/fiber/v3"
+	"github.com/golang-jwt/jwt/v5"
+)
+
+func GetCurrentUser(ctx context.Context) fiber.Handler {
+	return func(c fiber.Ctx) error {
+		authHeader := c.Get("Authorization")
+		if authHeader == "" {
+			return resp.R401(c, "MISSING_TOKEN", nil, "authorization token is required")
+		}
+
+		tokenString := authHeader
+		if len(authHeader) > 7 && authHeader[:7] == "Bearer " {
+			tokenString = authHeader[7:]
+		}
+
+		token, err := jwt.ParseWithClaims(tokenString, &Claims{}, func(token *jwt.Token) (interface{}, error) {
+			return []byte(JWTSecret), nil
+		})
+
+		if err != nil || !token.Valid {
+			return resp.R401(c, "INVALID_TOKEN", nil, "invalid or expired token")
+		}
+
+		claims, ok := token.Claims.(*Claims)
+		if !ok {
+			return resp.R401(c, "INVALID_CLAIMS", nil, "invalid token claims")
+		}
+
+		return resp.R200(c, map[string]interface{}{
+			"user_id":  claims.UserID,
+			"username": claims.Username,
+			"role":     claims.Role,
+		})
+	}
+}