feat(#248): expose parentId in TagTreeNodeDTO OpenAPI schema and regenerate TypeScript types

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/main/java/org/raddatz/familienarchiv/dto/TagTreeNodeDTO.java

@@ -3,4 +3,12 @@ package org.raddatz.familienarchiv.dto;
 import java.util.List;
 import java.util.UUID;
 
-public record TagTreeNodeDTO(UUID id, String name, String color, int documentCount, List<TagTreeNodeDTO> children, UUID parentId) {}
+import io.swagger.v3.oas.annotations.media.Schema;
+
+public record TagTreeNodeDTO(
+        UUID id,
+        String name,
+        String color,
+        int documentCount,
+        List<TagTreeNodeDTO> children,
+        @Schema(description = "Parent tag ID, null for root tags") UUID parentId) {}