refactor: remove empty services (#116)

* remove empty services

* remove old factory

* remove old static files

* cleanup more duplicate service code

* file/folder reorg

backend/internal/core/services/all.go

@@ -0,0 +1,24 @@
+package services
+
+import "github.com/hay-kot/homebox/backend/internal/data/repo"
+
+type AllServices struct {
+	User  *UserService
+	Group *GroupService
+	Items *ItemService
+}
+
+func New(repos *repo.AllRepos) *AllServices {
+	if repos == nil {
+		panic("repos cannot be nil")
+	}
+
+	return &AllServices{
+		User:  &UserService{repos},
+		Group: &GroupService{repos},
+		Items: &ItemService{
+			repo: repos,
+			at:   attachmentTokens{},
+		},
+	}
+}