Expose document history through pano cli

docs/modernization/roadmap.md

@@ -339,8 +339,10 @@ asset-level decode coverage, and
 counts, durations, and decoded face-pixel payload attachment when PPI image
 payloads are present.
 `pano_cli create-document` can create simple animation documents with explicit
-frame count/duration, and `pano_cli simulate-stroke` exercises the pure stroke
-sampler for scripted-stroke automation. `pano_cli simulate-stroke-script`
+frame count/duration. `pano_cli simulate-document-history` exercises the pure
+`pp_document::DocumentHistory` apply/undo/redo path and emits JSON state
+summaries. `pano_cli simulate-stroke` exercises the pure stroke sampler for
+scripted-stroke automation. `pano_cli simulate-stroke-script`
 loads stroke script fixtures, parses them through `pp_paint`, and samples every
 stroke. `pano_cli parse-layout` exercises the XML layout path. Continue
 expanding document behavior toward legacy Canvas parity and then port OpenGL
@@ -685,6 +687,8 @@ Results:
 - `pano_cli_create_document_smoke` passed.
 - `pano_cli_create_animation_document_smoke` passed and reports animation
   duration JSON.
+- `pano_cli_simulate_document_history_smoke` passed and reports real
+  `pp_document::DocumentHistory` apply/undo/redo state as JSON.
 - `pano_cli_inspect_image_rejects_unsupported` passed as an expected failure
   test.
 - `pano_cli_inspect_png_metadata_smoke` passed and reports PNG metadata JSON
@@ -746,6 +750,9 @@ Results:
 - `pano_cli record-render` exercises that headless recording renderer and emits
   JSON command counts, target dimensions, backend name, and trace/draw summary
   for agent automation.
+- `pano_cli simulate-document-history` exercises pure document history
+  apply/undo/redo behavior and emits JSON layer/frame/history state for agent
+  automation.
 - PowerShell package-smoke wrapper validates the Windows CMake app executable
   and runtime `data/` copy.
 - Android arm64 configured with NDK 29.0.14206865 through the platform-build