Centralize legacy document open bridge

docs/modernization/roadmap.md

@@ -728,6 +728,11 @@ layer-refresh, and action-history work remains tracked under `DEBT-0038`.
 `pano_cli parse-layout` exercises the XML layout path. Continue expanding
 document behavior toward legacy Canvas parity and then port OpenGL classes
 behind the renderer boundary.
+`App::open_document` now routes through the app-core document-open executor and
+`src/legacy_document_open_services.*`, preserving ABR/PPBR import prompts,
+unsaved-project discard prompts, project open, layer refresh, title updates,
+and history clearing while those live effects remain tracked under
+`DEBT-0039`.
 
 Implementation tasks:
 
@@ -1260,6 +1265,13 @@ Results:
 - `scripts/automation/package-smoke.ps1 -Preset windows-msvc-default
   -Configuration Debug` passed executable/data checks after the cloud bridge
   split; package target migration blockers remain under `DEBT-0011`.
+- `PanoPainter`, `pp_app_core_document_session_tests`, and `pano_cli` built
+  after `App::open_document` moved live execution behind the document-open
+  services bridge. A clean rebuild was required once because MSVC reported the
+  known Debug PDB `LNK1103` corruption, after which the build passed.
+- Focused document-open CTest coverage passed for
+  `pp_app_core_document_route_tests`, `pp_app_core_document_session_tests`, and
+  the `pano_cli_plan_open_route_*` smoke tests 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.