Add Visual Studio extension for Linux platform support

VSIX extension that adds:
- "OpenMaui Linux App" project template in File → New → Project
- Pre-configured launch profiles for Linux debugging
- WSL integration for Windows developers
- x64 and ARM64 build configurations

Launch Profiles included:
- Linux (Local) - Direct execution
- Linux (WSL) - Run via WSL
- Linux (x64 Release) - Release build for x64
- Linux (ARM64 Release) - Release build for ARM64
- Publish Linux x64/ARM64 - Self-contained publishing

Build with: msbuild /p:Configuration=Release
Output: OpenMaui.VisualStudio.vsix

vsix/OpenMaui.VisualStudio/source.extension.vsixmanifest

@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PackageManifest Version="2.0.0" xmlns="http://schemas.microsoft.com/developer/vsx-schema/2011" xmlns:d="http://schemas.microsoft.com/developer/vsx-schema-design/2011">
+  <Metadata>
+    <Identity Id="OpenMaui.VisualStudio.a1b2c3d4-e5f6-7890-abcd-ef1234567890" Version="1.0.0" Language="en-US" Publisher="MarketAlly LLC" />
+    <DisplayName>OpenMaui - Linux Platform for .NET MAUI</DisplayName>
+    <Description xml:space="preserve">Adds Linux platform support to .NET MAUI projects in Visual Studio. Build and deploy MAUI applications to Linux desktops with full SkiaSharp rendering support.
+
+Features:
+• Linux project templates
+• Linux build configurations
+• WSL debugging integration
+• Remote Linux debugging
+• Linux-specific launch profiles
+
+Developed by MarketAlly LLC
+Lead Architect: David H. Friedel Jr.</Description>
+    <MoreInfo>https://github.com/open-maui/maui-linux</MoreInfo>
+    <License>LICENSE.txt</License>
+    <GettingStartedGuide>https://github.com/open-maui/maui-linux/blob/main/docs/GETTING_STARTED.md</GettingStartedGuide>
+    <ReleaseNotes>https://github.com/open-maui/maui-linux/releases</ReleaseNotes>
+    <Icon>Resources\Icon.png</Icon>
+    <PreviewImage>Resources\Preview.png</PreviewImage>
+    <Tags>maui, linux, desktop, cross-platform, skia, openmaui, dotnet</Tags>
+  </Metadata>
+  <Installation>
+    <InstallationTarget Id="Microsoft.VisualStudio.Community" Version="[17.0,18.0)">
+      <ProductArchitecture>amd64</ProductArchitecture>
+    </InstallationTarget>
+    <InstallationTarget Id="Microsoft.VisualStudio.Pro" Version="[17.0,18.0)">
+      <ProductArchitecture>amd64</ProductArchitecture>
+    </InstallationTarget>
+    <InstallationTarget Id="Microsoft.VisualStudio.Enterprise" Version="[17.0,18.0)">
+      <ProductArchitecture>amd64</ProductArchitecture>
+    </InstallationTarget>
+  </Installation>
+  <Dependencies>
+    <Dependency Id="Microsoft.Framework.NDP" DisplayName="Microsoft .NET Framework" d:Source="Manual" Version="[4.8,)" />
+    <Dependency Id="Microsoft.VisualStudio.Component.CoreEditor" DisplayName="Visual Studio core editor" d:Source="Installed" Version="[17.0,18.0)" />
+    <Dependency Id="Microsoft.VisualStudio.Workload.NetCrossPlat" DisplayName=".NET MAUI Workload" d:Source="Installed" Version="[17.0,18.0)" />
+  </Dependencies>
+  <Prerequisites>
+    <Prerequisite Id="Microsoft.VisualStudio.Component.CoreEditor" Version="[17.0,18.0)" DisplayName="Visual Studio core editor" />
+  </Prerequisites>
+  <Assets>
+    <Asset Type="Microsoft.VisualStudio.ProjectTemplate" d:Source="File" Path="ProjectTemplates" d:TargetPath="ProjectTemplates" />
+    <Asset Type="Microsoft.VisualStudio.VsPackage" d:Source="Project" d:ProjectName="%CurrentProject%" Path="|%CurrentProject%;PkgdefProjectOutputGroup|" />
+  </Assets>
+</PackageManifest>