feat(lists): add direct user invitation to shared lists and streamline live-sync indicator

internal/storage/sqlite.go

@@ -606,14 +606,25 @@ func (s *Store) GetDiscoverableUsers(viewerID string) ([]domain.User, error) {
 		return []domain.User{*viewer}, nil
 	}
 
-	// teams_only: users sharing at least one team or organization with viewer
+	// teams_only: if no teams exist yet, allow discovering users on this instance
+	var teamCount int
+	_ = s.db.QueryRow(`SELECT COUNT(*) FROM teams`).Scan(&teamCount)
+	if teamCount == 0 {
+		return s.GetAllUsers()
+	}
+
+	// users sharing at least one team, organization or space with viewer
 	rows, err := s.db.Query(
 		`SELECT DISTINCT `+userSelectCols+` FROM users WHERE id = ? OR id IN (
 			SELECT tm2.user_id FROM team_members tm1
 			JOIN team_members tm2 ON tm1.team_id = tm2.team_id
 			WHERE tm1.user_id = ?
+			UNION
+			SELECT sm2.user_id FROM space_members sm1
+			JOIN space_members sm2 ON sm1.space_id = sm2.space_id
+			WHERE sm1.user_id = ?
 		)`,
-		viewerID, viewerID,
+		viewerID, viewerID, viewerID,
 	)
 	if err != nil {
 		return []domain.User{*viewer}, nil
@@ -1460,12 +1471,16 @@ func (s *Store) CreateDocShare(currentUserID, docID, targetUserIdentifier, permi
 		permission = "read"
 	}
 
-	// Resolve target user by ID or Email
+	// Resolve target user by ID, username, or Email
 	var targetUser *domain.User
 	cleanTarget := strings.TrimSpace(targetUserIdentifier)
-	if strings.Contains(cleanTarget, "@") {
-		targetUser, err = s.GetUserByEmail(cleanTarget)
-	} else {
+	if strings.HasPrefix(cleanTarget, "usr_") {
+		targetUser, _ = s.GetUserByID(cleanTarget)
+	}
+	if targetUser == nil {
+		targetUser, _ = s.GetUserByLogin(cleanTarget)
+	}
+	if targetUser == nil {
 		targetUser, err = s.GetUserByID(cleanTarget)
 	}
 	if err != nil || targetUser == nil {
@@ -1636,6 +1651,79 @@ func (s *Store) GetSpaceMembers(spaceID string) ([]domain.SpaceMember, error) {
 	return members, nil
 }
 
+func (s *Store) AddSpaceMember(currentUserID, spaceID, targetUserIdentifier, role string) (*domain.SpaceMember, error) {
+	// 1. Check if current user is member of space
+	var myRole string
+	err := s.db.QueryRow(`SELECT role FROM space_members WHERE space_id = ? AND user_id = ?`, spaceID, currentUserID).Scan(&myRole)
+	if err != nil {
+		return nil, errors.New("keine Berechtigung für diesen Bereich")
+	}
+
+	// 2. Resolve target user by ID, username or email
+	cleanTarget := strings.TrimSpace(targetUserIdentifier)
+	var targetUser *domain.User
+	if strings.HasPrefix(cleanTarget, "usr_") {
+		targetUser, _ = s.GetUserByID(cleanTarget)
+	}
+	if targetUser == nil {
+		targetUser, _ = s.GetUserByLogin(cleanTarget)
+	}
+	if targetUser == nil {
+		targetUser, err = s.GetUserByID(cleanTarget)
+	}
+	if err != nil || targetUser == nil {
+		return nil, errors.New("benutzer nicht gefunden")
+	}
+
+	if role != "owner" && role != "editor" && role != "viewer" {
+		role = "editor"
+	}
+
+	now := domain.NowISO()
+	_, err = s.db.Exec(
+		`INSERT INTO space_members (space_id, user_id, role, joined_at) VALUES (?, ?, ?, ?)
+		 ON CONFLICT(space_id, user_id) DO UPDATE SET role = excluded.role`,
+		spaceID, targetUser.ID, role, now,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return &domain.SpaceMember{
+		SpaceID:     spaceID,
+		UserID:      targetUser.ID,
+		DisplayName: targetUser.DisplayName,
+		Email:       targetUser.Email,
+		Role:        role,
+		JoinedAt:    now,
+	}, nil
+}
+
+func (s *Store) RemoveSpaceMember(currentUserID, spaceID, targetUserID string) error {
+	var myRole string
+	err := s.db.QueryRow(`SELECT role FROM space_members WHERE space_id = ? AND user_id = ?`, spaceID, currentUserID).Scan(&myRole)
+	if err != nil {
+		return errors.New("keine Berechtigung für diesen Bereich")
+	}
+
+	if currentUserID != targetUserID && myRole != "owner" {
+		return errors.New("nur der Eigentümer kann andere Mitglieder entfernen")
+	}
+
+	var targetRole string
+	_ = s.db.QueryRow(`SELECT role FROM space_members WHERE space_id = ? AND user_id = ?`, spaceID, targetUserID).Scan(&targetRole)
+	if targetRole == "owner" {
+		var ownerCount int
+		_ = s.db.QueryRow(`SELECT COUNT(*) FROM space_members WHERE space_id = ? AND role = 'owner'`, spaceID).Scan(&ownerCount)
+		if ownerCount <= 1 {
+			return errors.New("der letzte Eigentümer kann den Bereich nicht verlassen")
+		}
+	}
+
+	_, err = s.db.Exec(`DELETE FROM space_members WHERE space_id = ? AND user_id = ?`, spaceID, targetUserID)
+	return err
+}
+
 func (s *Store) GetSpacesForUser(userID string) ([]domain.Space, error) {
 	rows, err := s.db.Query(
 		`SELECT s.id, s.name, s.icon, s.description, s.invite_code, s.is_personal, s.owner_id, s.created_at