Add --version flag and tag-based version stamping for releases

[marcelloformica]

Changes

• C# EXE: Added --version\ / -v\ flag that prints \GetAvailability \ and exits, reading version from assembly metadata.
• PowerShell: Added -Version\ switch (via parameter sets so it works without mandatory params) that prints \get-availability \ and exits.
• Version default: Set <Version>0.0.0\ in the csproj and \ = '0.0.0-dev'\ in the PS1, so CI/local builds show 0.0.0.
• Release workflow: Extracts semver from the git tag (e.g. \�1.2.3\ → \1.2.3), passes -p:Version\ to \dotnet publish, and replaces \