feat(workspace): format origin callout date and time when converting thought to document

internal/storage/sqlite.go

@@ -812,6 +812,17 @@ func (s *Store) UpdateThoughtTriage(userID, thoughtID, action, convertTo, target
 				title = title[:72] + "…"
 			}
 			blocks := make([]domain.DocumentBlock, 0)
+			formattedDate := domain.FormatGermanDateTime(thought.CreatedAt)
+			calloutText := "Ursprünglicher Gedanke aus deiner Inbox"
+			if formattedDate != "" {
+				calloutText += " vom " + formattedDate
+			}
+			blocks = append(blocks, domain.DocumentBlock{
+				ID:      domain.NewID("blk"),
+				Type:    "callout",
+				Content: calloutText,
+				Level:   0,
+			})
 			if strings.TrimSpace(thought.Notes) != "" {
 				blocks = append(blocks, domain.DocumentBlock{
 					ID:      domain.NewID("blk"),
@@ -831,7 +842,7 @@ func (s *Store) UpdateThoughtTriage(userID, thoughtID, action, convertTo, target
 					})
 				}
 			}
-			if len(blocks) == 0 {
+			if len(blocks) == 1 {
 				blocks = append(blocks, domain.DocumentBlock{
 					ID:      domain.NewID("blk"),
 					Type:    "bullet",