Replace raw touch events with Windows Touch Gestures API

[Copilot]

Touch Input System Redesign - COMPLETED ✅

• Create new gesture event argument classes (GestureEventArgs with subclasses for each gesture type)
• Update ITouchControl interface to replace raw touch events with gesture events (Tap, Pan, Zoom, Rotate, TwoFingerTap, PressAndTap)
• Add native gesture interop structures and methods to WinFormsUtils.NativeMethods.cs
• Implement gesture message handling in WinFormsUtils.Touch.cs (replace raw touch handling with WM_GESTURE handling)
• Update TouchForm.cs to implement new gesture events
• Update TouchPanel.cs to implement new gesture events
• Remove obsolete TouchEventArgs.cs file (replaced by gesture event args)
• Code review and verification
• Security check (no vulnerabilities found)
• Use non-generic Marshal.SizeOf for .NET Framework compatibility

Summary

Successfully redesigned the touch input system from raw touch events to high-level Windows Touch Gestures. The implementation follows the Microsoft Windows classic samples and provides a clean, gesture-based API for WinForms applications on Windows 7+.

Key Changes:

• Events: Replaced TouchDown, TouchUp, TouchMove with Pan, Zoom, Rotate, Tap, PressAndTap
• Native Code: All gesture interop code is cleanly isolated in WinFormsUtils.Touch.cs
• API Design: Each gesture has its own strongly-typed event args with relevant properties
• Compatibility: Maintained API structure while switching underlying implementation, using non-generic Marshal.SizeOf for .NET Framework compatibility

Original prompt

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This section details on the original issue you should resolve

<issue_title>Redesign touch input system</issue_title>
<issue_description>This project contains incomplete code for adding touch support to WinForms projects. This code lives in:

• src/Common.WinForms/Controls/ITouchControl.cs
• src/Common.WinForms/Controls/TouchForm.cs
• src/Common.WinForms/Controls/TouchPanel.cs
• src/Common.WinForms/Native/WinFormsUtils.Touch.cs

Currently it tries to represent raw touch events. We should redesign this to expose the higher-level Windows Touch Gestures instead.

Replace the delegates in ITouchControl and its implementations from TouchDown, TouchUp and TouchMove with Tap, Pan, Zoom, etc..

Look at https://github.com/microsoft/Windows-classic-samples/blob/main/Samples/Win7Samples/Touch/MTGestures/CS/MTGestures.cs for details how the native interop works.
In our own implementation we want to keep all the native code nicely isolated in WinFormsUtils.Touch.cs.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Redesign touch input system #195

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[bastianeicher]

Use the non-generic variant of Marshal.SizeOf, so that the code also compiles on .NET Framework.

[Copilot]

Use the non-generic variant of Marshal.SizeOf, so that the code also compiles on .NET Framework.

Changed to use Marshal.SizeOf(typeof(T)) instead of the generic variant in commit 49e8ed5.