feat(mcp): delete tasks, create task lists and lists, agent badge; export/import settings category

New MCP tools delete_task (tasks:write), create_task_list (tasks:write) and create_list
(lists:write); list_task_lists now returns the board columns so agents know the valid
kanbanStatus values. Task deletion is a shared helper (deleteTask) for REST and MCP.

Tasks and list items get agent_mark (migration 12): "created" when an agent adds them via MCP,
"edited" when an agent changes them; a change by the user clears it. The new AgentBadge shows
"KI" / "KI geändert" in task rows, Kanban cards, the task detail, the inbox and lists.

Settings: export and import move out of "Webhooks, KI-Agenten & Export" into their own
category "Export & Import". Docs, help, README and changelog updated; v0.29.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/storage/thoughts.go

@@ -76,11 +76,14 @@ func (s *Store) CreateThoughtWithDetails(userID, content, priority, source, dueD
 		Notes:        notes,
 		CreatedAt:    domain.NowISO(),
 	}
+	if source == "agent" {
+		t.AgentMark = AgentMarkCreated
+	}
 
 	_, err := s.db.Exec(
-		`INSERT INTO thoughts (id, user_id, content, tags, priority, source, status, is_completed, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, subtasks)
-		 VALUES (?, ?, ?, ?, ?, ?, ?, 0, ?, ?, ?, ?, 0, ?, '[]')`,
-		t.ID, t.UserID, t.Content, string(tagsJSON), t.Priority, t.Source, string(t.Status), t.DueDate, t.TaskListID, t.KanbanStatus, t.Notes, t.CreatedAt,
+		`INSERT INTO thoughts (id, user_id, content, tags, priority, source, status, is_completed, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, subtasks, agent_mark)
+		 VALUES (?, ?, ?, ?, ?, ?, ?, 0, ?, ?, ?, ?, 0, ?, '[]', ?)`,
+		t.ID, t.UserID, t.Content, string(tagsJSON), t.Priority, t.Source, string(t.Status), t.DueDate, t.TaskListID, t.KanbanStatus, t.Notes, t.CreatedAt, t.AgentMark,
 	)
 	if err != nil {
 		return nil, err
@@ -99,7 +102,7 @@ func scanThought(rows interface {
 		&t.ID, &t.UserID, &t.Content, &tagsStr, &t.Priority, &t.Source,
 		&statusStr, &isCompleted, &t.ConvertedType, &t.ConvertedRefID,
 		&t.DueDate, &t.TaskListID, &t.KanbanStatus, &t.Notes, &alarmSent,
-		&t.CreatedAt, &t.TriagedAt, &subtasksStr, &sortOrder, &t.Recurrence,
+		&t.CreatedAt, &t.TriagedAt, &subtasksStr, &sortOrder, &t.Recurrence, &t.AgentMark,
 	)
 	if err != nil {
 		return nil, err
@@ -136,7 +139,7 @@ func (s *Store) accessibleTaskListIDsQuery() string {
 
 func (s *Store) GetThoughtByID(userID, thoughtID string) (*domain.Thought, error) {
 	row := s.db.QueryRow(
-		`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence
+		`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence, agent_mark
 		 FROM thoughts WHERE id = ? AND (user_id = ? OR task_list_id IN (`+s.accessibleTaskListIDsQuery()+`))`,
 		thoughtID, userID, userID, userID, userID,
 	)
@@ -157,14 +160,14 @@ func (s *Store) GetThoughts(userID, statusFilter string, limit int) ([]domain.Th
 
 	if statusFilter != "" && statusFilter != "all" {
 		rows, err = s.db.Query(
-			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence
+			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence, agent_mark
 			 FROM thoughts WHERE user_id = ? AND status = ?
 			 ORDER BY CASE priority WHEN 'urgent' THEN 1 WHEN 'high' THEN 2 WHEN 'normal' THEN 3 ELSE 4 END, sort_order ASC, created_at DESC LIMIT ?`,
 			userID, statusFilter, limit,
 		)
 	} else {
 		rows, err = s.db.Query(
-			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence
+			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence, agent_mark
 			 FROM thoughts WHERE user_id = ?
 			 ORDER BY sort_order ASC, created_at DESC LIMIT ?`,
 			userID, limit,
@@ -190,7 +193,7 @@ func (s *Store) GetTasks(userID string, taskListID string) ([]domain.Thought, er
 	var err error
 	if taskListID != "" {
 		rows, err = s.db.Query(
-			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence
+			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence, agent_mark
 			 FROM thoughts
 			 WHERE (user_id = ? OR task_list_id IN (`+s.accessibleTaskListIDsQuery()+`))
 			   AND task_list_id = ?
@@ -200,7 +203,7 @@ func (s *Store) GetTasks(userID string, taskListID string) ([]domain.Thought, er
 		)
 	} else {
 		rows, err = s.db.Query(
-			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence
+			`SELECT id, user_id, content, tags, priority, source, status, is_completed, converted_type, converted_ref_id, due_date, task_list_id, kanban_status, notes, alarm_sent, created_at, triaged_at, subtasks, sort_order, recurrence, agent_mark
 			 FROM thoughts
 			 WHERE (user_id = ? OR task_list_id IN (`+s.accessibleTaskListIDsQuery()+`))
 			   AND (status = 'kept' OR (status = 'converted' AND converted_type = 'task'))
@@ -509,6 +512,59 @@ func (s *Store) DeleteThought(userID, thoughtID string) error {
 	return err
 }
 
+// migrateAgentMark: entries an AI agent created or changed via MCP and the user has not touched since
+func (s *Store) migrateAgentMark() error {
+	if err := s.addColumnIfMissing("thoughts", "agent_mark", "TEXT NOT NULL DEFAULT ''"); err != nil {
+		return err
+	}
+	return s.addColumnIfMissing("list_items", "agent_mark", "TEXT NOT NULL DEFAULT ''")
+}
+
+// Values of agent_mark on thoughts and list items
+const (
+	AgentMarkCreated = "created"
+	AgentMarkEdited  = "edited"
+)
+
+// nextAgentMark: an agent's change marks the entry (an entry it created stays "created"), a change by
+// the user removes the mark.
+func nextAgentMark(current string, byAgent bool) string {
+	if !byAgent {
+		return ""
+	}
+	if current == AgentMarkCreated {
+		return AgentMarkCreated
+	}
+	return AgentMarkEdited
+}
+
+// SetThoughtAgentMark records who changed a task last and returns the new mark.
+func (s *Store) SetThoughtAgentMark(thoughtID, current string, byAgent bool) string {
+	mark := nextAgentMark(current, byAgent)
+	if mark != current {
+		_, _ = s.db.Exec(`UPDATE thoughts SET agent_mark = ? WHERE id = ?`, mark, thoughtID)
+	}
+	return mark
+}
+
+// SetListItemAgentMark is SetThoughtAgentMark for list items; the current mark is read here because
+// the item queries after a change do not carry it.
+func (s *Store) SetListItemAgentMark(itemID string, byAgent bool) string {
+	var current string
+	_ = s.db.QueryRow(`SELECT agent_mark FROM list_items WHERE id = ?`, itemID).Scan(&current)
+	mark := nextAgentMark(current, byAgent)
+	if mark != current {
+		_, _ = s.db.Exec(`UPDATE list_items SET agent_mark = ? WHERE id = ?`, mark, itemID)
+	}
+	return mark
+}
+
+// MarkListItemAgentCreated marks an item an agent just added.
+func (s *Store) MarkListItemAgentCreated(itemID string) string {
+	_, _ = s.db.Exec(`UPDATE list_items SET agent_mark = ? WHERE id = ?`, AgentMarkCreated, itemID)
+	return AgentMarkCreated
+}
+
 func (s *Store) PurgeDiscardedThoughts(userID string) (int64, error) {
 	res, err := s.db.Exec(`DELETE FROM thoughts WHERE user_id = ? AND status = 'discarded'`, userID)
 	if err != nil {