fix: Project checks (#141)

* project validations

* unique project on resourceowner

internal/project/repository/eventsourcing/model/project.go

@@ -21,6 +21,15 @@ type Project struct {
 	Grants       []*ProjectGrant  `json:"-"`
 }
 
+func GetProject(projects []*Project, id string) (int, *Project) {
+	for i, p := range projects {
+		if p.AggregateID == id {
+			return i, p
+		}
+	}
+	return -1, nil
+}
+
 func (p *Project) Changes(changed *Project) map[string]interface{} {
 	changes := make(map[string]interface{}, 1)
 	if changed.Name != "" && p.Name != changed.Name {