Centralize legacy brush package export

docs/modernization/roadmap.md

@@ -778,6 +778,12 @@ executor and `src/legacy_document_export_services.*`, preserving mobile/Web
 suggested-name save callbacks, desktop worker-thread timelapse export,
 `App::rec_export`, animation `Canvas::export_anim_mp4` dispatch, and existing
 success messages while retained execution remains tracked under `DEBT-0044`.
+`App::dialog_ppbr_export` now routes picker-selected PPBR brush package exports
+through the app-core brush package export executor and
+`src/legacy_brush_package_export_services.*`, preserving dialog metadata
+collection, legacy `Image` header ownership, desktop worker-thread export,
+mobile/Web save completion, `NodePanelBrushPreset::export_ppbr`, and existing
+success messages while retained execution remains tracked under `DEBT-0047`.
 
 Implementation tasks:
 
@@ -1369,6 +1375,14 @@ Results:
 - Focused startup CTest coverage passed for `pp_app_core_app_startup_tests`,
   `pano_cli_plan_app_startup_smoke`, and
   `pano_cli_plan_app_startup_rejects_negative_counter`.
+- `PanoPainter`, `pp_app_core_brush_package_export_tests`, and `pano_cli` built
+  after PPBR brush package export request validation and dispatch moved behind
+  app-core brush package services.
+- Focused PPBR export CTest coverage passed for
+  `pp_app_core_brush_package_export_tests`,
+  `pano_cli_plan_brush_package_export_smoke`,
+  `pano_cli_plan_brush_package_export_rejects_empty_path`, and
+  `pano_cli_plan_brush_package_export_dest_without_data_smoke`.
 - `pp_app_core_document_recording_tests` passed, covering recording start/stop,
   clear, platform recorded-file cleanup, frame-count reset, export progress
   totals, and oversized progress-total clamping.