Centralize legacy document image exports

docs/modernization/roadmap.md

@@ -750,6 +750,14 @@ Save Version plans through app-core document file/version save executors and
 legacy `Canvas::project_save`, app document field updates, title updates, and
 keyboard/dialog cleanup while retained execution remains tracked under
 `DEBT-0042`.
+`App::dialog_export`, `App::dialog_export_layers`,
+`App::dialog_export_anim_frames`, `App::dialog_export_depth`, and
+`App::dialog_export_cube_faces` now route accepted file/stem/collection and
+named export work through app-core document export executors and
+`src/legacy_document_export_services.*`, preserving existing platform messages,
+directory creation, picker-selected stems, Web prepared-file handoff, and legacy
+`Canvas` export calls while retained execution remains tracked under
+`DEBT-0043`.
 
 Implementation tasks:
 
@@ -1314,6 +1322,14 @@ Results:
   `pp_app_core_document_session_tests`, `pano_cli_plan_document_file_*`,
   `pano_cli_plan_document_version_*`, and `pano_cli_simulate_app_session_*`
   smoke tests after the live bridge split.
+- `PanoPainter`, `pp_app_core_document_export_tests`, and `pano_cli` built
+  after equirectangular, layers, animation-frame, depth, and cube-face export
+  execution moved behind document export services. A clean rebuild was required
+  once because MSVC reported the known Debug PDB `LNK1103` corruption, after
+  which the build passed.
+- Focused export CTest coverage passed for `pp_app_core_document_export_tests`,
+  `pano_cli_plan_export_start/menu/target_*`, and
+  `pano_cli_simulate_document_export_smoke` after the live bridge split.
 - `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.