StartupManager now falls back to the Run registry key when the MSIX StartupTask
API is unavailable, so the tray toggle works in the classic installer build and
stays consistent with the installer-set Run value.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CWindowImpl asserts (m_hWnd must be NULL) if the C++ object is deleted while
its HWND is still alive. On Exit the window was only ever hidden (WM_CLOSE),
never destroyed, so 'delete g_calc' tripped the ATL debug assertion. Destroy
the window first.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

The window was sized to the text extent only, so the caption consumed the
whole height and the EDIT was invisible. Use AdjustWindowRectEx on the desired
client size (min 160x28), fill the client with the EDIT, shorten the title.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

The TaskbarCalculatorSetup.vdproj (VS Setup & Deployment project) is not
supported in VS2022 and is superseded by the MSIX packaging in Packaging/.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

- AppxManifest.xml with windows.startupTask (TaskbarCalculatorStartup)
- MakeAssets/MakeCert/BuildMsix scripts, generated logo assets
- gitignore layout/, *.pfx, *.msix

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

- Delete COM/DeskBand sources, .def, .rgs, .idl, Guids.h, MFC AboutDialog
- Rewrite vcxproj as Application (v143, SDK 26100, C++17, no MIDL)
- Remove REGISTRY .rgs reference from .rc
- Add stub App.cpp with wWinMain
- CalculatorWindow.cpp excluded from build until Task 10 rework

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>