Add Linux app package readiness

docs/modernization/build-inventory.md

@@ -184,18 +184,18 @@ powershell -ExecutionPolicy Bypass -File scripts\automation\apple-remote-build.p
   It also guards the root CMake platform automation target names and the
   PowerShell/shell Android SDK Manager update hooks.
 - `package-smoke.ps1 -ReadinessOnly` and `package-smoke.sh --readiness-only`
-  emit the Windows AppX, Android standard/Quest/Focus APK, Apple bundle, and
-  WebGL package readiness matrix without first building an app artifact. The
-  full package smoke command still builds/checks the selected app target before
-  reporting the same readiness matrix. `package-smoke.ps1
+  emit the Windows AppX, Android standard/Quest/Focus APK, Apple bundle, Linux
+  app, and WebGL package readiness matrix without first building an app
+  artifact. The full package smoke command still builds/checks the selected app
+  target before reporting the same readiness matrix. `package-smoke.ps1
   -AndroidNativeChecks` also runs the retained Android standard `native-lib`
   build and Quest/Focus configure helper for selected Android package kinds,
   then reports those native results beside the APK blocker matrix.
   `scripts/dev/check_package_smoke_readiness.py`, registered as
   `panopainter_package_smoke_readiness_self_test`, verifies both wrappers keep
-  the same six package kinds, blocked DEBT-0011 status, readiness-only mode,
-  retained Android native-check prerequisite metadata, and root CMake package
-  validation target names.
+  the same seven package kinds, blocked DEBT-0011 status, readiness-only mode,
+  retained Android native-check prerequisite metadata, retained Linux/WebGL
+  CMake baseline metadata, and root CMake package validation target names.
 - Root CMake exposes non-default package validation targets:
   `panopainter_package_readiness`,
   `panopainter_windows_app_package_smoke`,

docs/modernization/debt.md

@@ -31,8 +31,8 @@ agent or engineer to remove them without reconstructing context from chat.
   Android variants. Package targets remain open under DEBT-0009 and DEBT-0011.
 - 2026-06-05: DEBT-0011 was narrowed. `package-smoke.ps1` and
   `package-smoke.sh` now have readiness-only modes that report the same
-  Windows AppX, Android standard/Quest/Focus APK, Apple bundle, and WebGL
-  blocker matrix without requiring an app build first, and
+  Windows AppX, Android standard/Quest/Focus APK, Apple bundle, Linux app, and
+  WebGL blocker matrix without requiring an app build first, and
   `panopainter_package_smoke_readiness_self_test` guards package-kind parity
   across both wrappers. Package target migration remains open.
 - 2026-06-05: DEBT-0004 was narrowed for Apple compile coverage. The Mac mini
@@ -269,6 +269,11 @@ agent or engineer to remove them without reconstructing context from chat.
   instead of global C++14 flags. `panopainter_retained_platform_cmake_self_test`
   guards those baselines while root CMake app/package target migration remains
   open.
+- 2026-06-05: DEBT-0011 was narrowed again. Package readiness now includes a
+  Linux app output blocker and points WebGL readiness at the retained WebGL app
+  CMake entrypoint, with both PowerShell and shell wrappers reporting the
+  retained Linux/WebGL CMake baseline prerequisite guarded by
+  `panopainter_retained_platform_cmake_self_test`.
 - 2026-06-05: DEBT-0011 was narrowed again. `package-smoke.ps1` now has
   `-AndroidNativeChecks`, which invokes the retained Android standard
   `native-lib` build and Quest/Focus configure helper for selected Android
@@ -323,7 +328,7 @@ agent or engineer to remove them without reconstructing context from chat.
 | DEBT-0008 | Open | Modernization | `windows-msvc-default` preset is used for local validation because the VS 2026 generator is not installed here | The target VS 2026 preset must remain, but this machine configures with Visual Studio 17 2022 | `cmake --preset windows-msvc-default`; `ctest --preset desktop-fast --build-config Debug` | Validate `windows-vs2026-x64` on a machine with Visual Studio 2026 installed and make it the default Windows validation preset |
 | DEBT-0009 | Open | Modernization | Android root CMake validation currently builds headless targets only, while retained standard/Quest/Focus package CMake paths now have a refreshed CMake 3.10/C++23 baseline outside root CMake; automation queries `sdkmanager`, installs newer or missing SDK Manager NDK/CMake packages, selects the resulting pair before configure, and reports update decisions; root CMake exposes non-default platform-build and retained native package validation targets | Platform app entrypoints still live in legacy Gradle/CMake projects and need Phase 6 alignment | `powershell -ExecutionPolicy Bypass -File scripts\automation\platform-build.ps1 -Presets android-arm64`; `cmake --build --preset android-x64`; `cmake --build --preset android-quest-arm64`; `cmake --build --preset android-focus-arm64`; `cmake --build --preset windows-msvc-default --config Debug --target panopainter_platform_build_android_assets`; `powershell -ExecutionPolicy Bypass -File scripts\automation\android-legacy-package-build.ps1 -Packages standard`; `powershell -ExecutionPolicy Bypass -File scripts\automation\android-legacy-package-build.ps1 -Packages quest,focus -ConfigureOnly`; `powershell -ExecutionPolicy Bypass -File scripts\automation\package-smoke.ps1 -ReadinessOnly -AndroidNativeChecks -PackageKinds android-standard-apk,android-quest-apk,android-focus-apk`; `cmake --build --preset windows-msvc-default --config Debug --target panopainter_android_native_package_smoke` | Android standard, Quest, and Focus/Wave package targets consume shared component targets and have package smoke commands |
 | DEBT-0010 | Open | Modernization | `pp_document` is a pure layer/frame/document/undo-history model with alpha-lock metadata, snapshot construction, per-layer frame metadata, renderer-free RGBA8 face payload storage, snapshot-embedded face-payload validation, renderer-free alpha8 selection-mask storage, PPI import/export helpers, and stroke-script-to-face-payload CLI automation, but it is not yet wired to legacy `Canvas`, legacy save, or legacy action commands | Keep extraction incremental while preserving app behavior | `ctest --preset desktop-fast --build-config Debug`; `pano_cli create-document --width 64 --height 32 --layers 2`; `pano_cli load-project --path tests\data\projects\minimal-project.ppi`; `pp_document_tests`; `pp_document_ppi_import_tests`; `pp_document_ppi_export_tests`; `pano_cli_simulate_document_edits_smoke`; `pano_cli_simulate_document_export_smoke`; `pano_cli_save_document_project_roundtrip_smoke`; `pano_cli_apply_stroke_script_roundtrip_smoke`; `pano_cli_apply_stroke_script_rejects_tiny_canvas` | Legacy document behavior is represented by `pp_document` tests and the app consumes it through a boundary/facade |
-| DEBT-0011 | Open | Modernization | `package-smoke` validates the Windows CMake app artifact and reports a structured package readiness matrix for Windows AppX, Android standard/Quest/Focus APKs, Apple bundles, and WebGL output; the Windows app smoke and retained Android package native CMake paths are reachable from root CMake package validation targets, but Windows AppX/APK/Apple/WebGL package outputs are still `blocked` because root CMake package targets do not exist yet | Platform package targets are not migrated to root CMake yet | `powershell -ExecutionPolicy Bypass -File scripts\automation\package-smoke.ps1 -Preset windows-msvc-default -Configuration Debug`; `cmake --build --preset windows-msvc-default --config Debug --target panopainter_windows_app_package_smoke`; `powershell -ExecutionPolicy Bypass -File scripts\automation\package-smoke.ps1 -ReadinessOnly -AndroidNativeChecks -PackageKinds android-standard-apk,android-quest-apk,android-focus-apk`; `cmake --build --preset windows-msvc-default --config Debug --target panopainter_android_native_package_smoke`; `python scripts/dev/check_package_smoke_readiness.py`; `bash -n scripts/automation/package-smoke.sh` | Package-smoke builds and validates Windows AppX, Android APK variants, Apple bundles, and WebGL output where local toolchains are present |
+| DEBT-0011 | Open | Modernization | `package-smoke` validates the Windows CMake app artifact and reports a structured package readiness matrix for Windows AppX, Android standard/Quest/Focus APKs, Apple bundles, Linux app output, and WebGL output; the Windows app smoke, retained Android package native CMake paths, and retained Linux/WebGL CMake baseline metadata are reachable from package validation, but Windows AppX/APK/Linux/Apple/WebGL package outputs are still `blocked` because root CMake package targets do not exist yet | Platform package targets are not migrated to root CMake yet | `powershell -ExecutionPolicy Bypass -File scripts\automation\package-smoke.ps1 -Preset windows-msvc-default -Configuration Debug`; `cmake --build --preset windows-msvc-default --config Debug --target panopainter_windows_app_package_smoke`; `powershell -ExecutionPolicy Bypass -File scripts\automation\package-smoke.ps1 -ReadinessOnly -AndroidNativeChecks -PackageKinds android-standard-apk,android-quest-apk,android-focus-apk`; `cmake --build --preset windows-msvc-default --config Debug --target panopainter_android_native_package_smoke`; `python scripts/dev/check_package_smoke_readiness.py`; `bash -n scripts/automation/package-smoke.sh` | Package-smoke builds and validates Windows AppX, Android APK variants, Linux app, Apple bundles, and WebGL output where local toolchains are present |
 | DEBT-0012 | Open | Modernization | `pp_ui_core` uses vcpkg tinyxml2 on `windows-msvc-vcpkg-headless`, but retains `pp_vendor_tinyxml2` for default and unproven platform presets | Mobile/AppX/Apple triplets and app packaging still need validation before removing the vendored fallback | `ctest --preset desktop-fast-vcpkg --build-config Debug`; `ctest --preset desktop-fast --build-config Debug`; `powershell -ExecutionPolicy Bypass -File scripts\automation\platform-build.ps1 -Presets android-arm64` | All supported presets consume vcpkg tinyxml2 or document a permanent vendored exception |
 | DEBT-0013 | Open | Modernization | `pp_assets`, `pp_document`, `pano_cli inspect-project`, `pano_cli load-project`, and `pano_cli save-project` validate the fixed PPI header, thumbnail/body byte layout, generated multi-layer/multi-frame PPI writing with explicit layer opacity/blend/alpha-lock/visibility metadata, per-layer frame durations, metadata-only and targeted dirty-face-payload save/load round-trips, layer/frame index, dirty-face descriptors, dirty-face PNG payload metadata, asset-level RGBA PNG payload decoding, pure document-to-PPI export, CLI document export automation, file-writing document export automation, stroke-script-generated document payload export, and decoded pixel attachment to `pp_document`, but full legacy PPI round-trip parity is not yet extracted | Full PPI save parity requires staged extraction of legacy `Canvas` serialization and image/layer payload handling | `ctest --preset desktop-fast --build-config Debug`; `pp_assets_image_pixels_tests`; `pp_assets_ppi_header_tests`; `pp_document_ppi_import_tests`; `pp_document_ppi_export_tests`; `pano_cli_inspect_project_layout_smoke`; `pano_cli_load_project_metadata_smoke`; `pano_cli_save_project_roundtrip_smoke`; `pano_cli_save_project_payload_roundtrip_smoke`; `pano_cli_simulate_document_export_smoke`; `pano_cli_save_document_project_roundtrip_smoke`; `pano_cli_apply_stroke_script_roundtrip_smoke`; `pano_cli_apply_stroke_script_rejects_tiny_canvas` | Full PPI load/save fixtures cover thumbnails, decoded layer face payloads attached to documents, frames, corrupt payloads, dirty-face payload saving, arbitrary legacy canvas payload/layout combinations, and legacy app round-trip compatibility |
 | DEBT-0014 | Open | Modernization | `windows-clangcl-asan` now configures as a headless Ninja/clang-cl preset and uses the release MSVC runtime required by ASan, but local builds still fail because installed clang-cl 18.1.8 is paired with VS 2026-preview STL headers that require Clang 20 or newer | Sanitizer validation should be local and repeatable, but this machine's compiler/header pairing is incompatible | `cmake --fresh --preset windows-clangcl-asan`; `cmake --build --preset windows-clangcl-asan --target pp_foundation` | Install/use Clang 20+ with the VS 2026 STL, or point the preset at a compatible VS 2022 toolchain, then make `platform-build.ps1 -Presets windows-clangcl-asan` pass for the headless matrix |

docs/modernization/roadmap.md

@@ -1396,11 +1396,12 @@ also exposes non-default platform validation targets:
 those target names and the wrapper matrix now includes
 `pp_app_core_app_dialog_tests` with the rest of the CMake test executables.
 `package-smoke` now emits a structured package readiness matrix for Windows
-AppX, Android standard/Quest/Focus APKs, Apple bundles, and WebGL output, with
-blocked prerequisites tied to DEBT-0011. It also has a readiness-only mode for
-cheap package blocker inventory without building an app artifact, and
-`panopainter_package_smoke_readiness_self_test` keeps the PowerShell and shell
-readiness matrices aligned. The PowerShell wrapper can also run the retained
+AppX, Android standard/Quest/Focus APKs, Apple bundles, Linux app output, and
+WebGL output, with blocked prerequisites tied to DEBT-0011. It also has a
+readiness-only mode for cheap package blocker inventory without building an app
+artifact, and `panopainter_package_smoke_readiness_self_test` keeps the
+PowerShell and shell readiness matrices aligned, including retained Linux/WebGL
+CMake baseline metadata. The PowerShell wrapper can also run the retained
 Android native package checks through `-AndroidNativeChecks`, reporting the
 standard `native-lib` build plus Quest/Focus configure checks next to the APK
 blocker matrix. Root CMake now exposes non-default package validation targets
@@ -2388,11 +2389,12 @@ Results:
   document export or history can persist malformed state.
 - Package-smoke wrappers validate the Windows CMake app executable/runtime
   `data/` copy and report structured package readiness for AppX, Android
-  standard/Quest/Focus APKs, Apple bundles, and WebGL outputs. Actual package
-  building remains blocked by DEBT-0011 until those targets are migrated to
-  root CMake. Readiness-only mode now reports the same matrix without building
-  the app first, and the package readiness self-test keeps wrapper package
-  kinds aligned.
+  standard/Quest/Focus APKs, Apple bundles, Linux app output, and WebGL
+  outputs. Actual package building remains blocked by DEBT-0011 until those
+  targets are migrated to root CMake. Readiness-only mode now reports the same
+  matrix without building the app first, and the package readiness self-test
+  keeps wrapper package kinds, retained Linux/WebGL CMake metadata, and blocker
+  metadata aligned.
 - Android standard arm64/x64, Quest arm64, and Focus/Wave arm64 configure
   through the platform-build wrapper by default. Focused validation compiled
   representative headless component/tool targets across all four presets, and