[client, management] Add new network concept (#3047)

---------

Co-authored-by: Pascal Fischer <32096965+pascal-fischer@users.noreply.github.com>
Co-authored-by: bcmmbaga <bethuelmbaga12@gmail.com>
Co-authored-by: Maycon Santos <mlsmaycon@gmail.com>
Co-authored-by: Zoltan Papp <zoltan.pmail@gmail.com>

management/server/users/manager.go

@@ -0,0 +1,49 @@
+package users
+
+import (
+	"context"
+	"errors"
+
+	"github.com/netbirdio/netbird/management/server/store"
+	"github.com/netbirdio/netbird/management/server/types"
+)
+
+type Manager interface {
+	GetUser(ctx context.Context, userID string) (*types.User, error)
+}
+
+type managerImpl struct {
+	store store.Store
+}
+
+type managerMock struct {
+}
+
+func NewManager(store store.Store) Manager {
+	return &managerImpl{
+		store: store,
+	}
+}
+
+func (m *managerImpl) GetUser(ctx context.Context, userID string) (*types.User, error) {
+	return m.store.GetUserByUserID(ctx, store.LockingStrengthShare, userID)
+}
+
+func NewManagerMock() Manager {
+	return &managerMock{}
+}
+
+func (m *managerMock) GetUser(ctx context.Context, userID string) (*types.User, error) {
+	switch userID {
+	case "adminUser":
+		return &types.User{Id: userID, Role: types.UserRoleAdmin}, nil
+	case "regularUser":
+		return &types.User{Id: userID, Role: types.UserRoleUser}, nil
+	case "ownerUser":
+		return &types.User{Id: userID, Role: types.UserRoleOwner}, nil
+	case "billingUser":
+		return &types.User{Id: userID, Role: types.UserRoleBillingAdmin}, nil
+	default:
+		return nil, errors.New("user not found")
+	}
+}