refactor: repositories (#28)

* cleanup unnecessary mocks

* refactor document storage location

* remove unused function

* move ownership to document types to repo package

* move types and mappers to repo package

* refactor sets to own package

backend/pkgs/set/set.go

@@ -0,0 +1,56 @@
+package set
+
+type key interface {
+	comparable
+}
+
+type Set[T key] struct {
+	mp map[T]struct{}
+}
+
+func New[T key](v ...T) Set[T] {
+	mp := make(map[T]struct{}, len(v))
+
+	s := Set[T]{mp}
+
+	s.Insert(v...)
+	return s
+}
+
+func (s Set[T]) Insert(v ...T) {
+	for _, e := range v {
+		s.mp[e] = struct{}{}
+	}
+}
+
+func (s Set[T]) Remove(v ...T) {
+	for _, e := range v {
+		delete(s.mp, e)
+	}
+}
+
+func (s Set[T]) Contains(v T) bool {
+	_, ok := s.mp[v]
+	return ok
+}
+
+func (s Set[T]) ContainsAll(v ...T) bool {
+	for _, e := range v {
+		if !s.Contains(e) {
+			return false
+		}
+	}
+	return true
+}
+
+func (s Set[T]) Slice() []T {
+	slice := make([]T, 0, len(s.mp))
+	for k := range s.mp {
+		slice = append(slice, k)
+	}
+	return slice
+}
+
+func (s Set[T]) Len() int {
+	return len(s.mp)
+}