Add framework-dependent deployment packages without bundled .NET runtime

[Copilot]

Adds framework-dependent installation packages for users with .NET 9.0 already installed, reducing download size by ~150-200MB.

Changes

Build configuration:

• Added Net9.0-FrameworkDependent.pubxml publish profile with SelfContained=false, outputs to Output/Release-FD
• Enhanced post_build.ps1 to build both deployment modes in sequence

Package outputs:

• Self-contained (existing): Flow-Launcher-Setup.exe, Flow-Launcher-Portable.zip
• Framework-dependent (new): Flow-Launcher-Setup-FD.exe, Flow-Launcher-Portable-FD.zip

CI/CD:

• Updated GitHub Actions and AppVeyor workflows to upload both package types as separate artifacts
• Both package types included in release deployments

Documentation:

• Updated README installation section with framework-dependent package links

Technical notes

Framework-dependent packages require .NET 9.0 runtime pre-installed on target systems. Build process handles nupkg naming conflicts by appending -FD suffix before Squirrel releasify step.

Original prompt

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This section details on the original issue you should resolve

<issue_title>FEATURE REQUEST: provide an installation package that does not include the .NET runtime.</issue_title>
<issue_description>Provides an installation package that does not include the .NET runtime to reduce the package size.</issue_description>

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

• Fixes FEATURE REQUEST: provide an installation package that does not include the .NET runtime. #4134

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