Initialize repository structure following serde.msgpack template

[Copilot]

Sets up fixed-width repository with build infrastructure, workflows, and empty project scaffolding per serde.msgpack pattern.

Structure

• Build system: Directory.Build.{props,targets}, Directory.Packages.props with central package management
• Projects: Serde.FixedWidth (library), Serde.FixedWidth.Tests (tests), bench (benchmarks) - all empty, no implementation
• CI/CD: GitHub Actions workflows (ci, pack, publish) with explicit permissions and current action versions (v4)
• Development: Comprehensive .gitignore, BSD 3-Clause license

Package Configuration

<PackageVersion Include="Serde" Version="[0.8.0-preview8]" />
<PackageVersion Include="xunit" Version="2.9.0" />
<PackageVersion Include="BenchmarkDotNet" Version="0.14.0" />

Solution builds, tests run (no tests defined), and packs to Serde.FixedWidth.0.1.0-preview1.nupkg.

Original prompt

Please set up this repo like https://github.com/serdedotnet/serde.msgpack, but with no source code or tests to start

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✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[agocke]

@copilot Please delete the vscode stuff

[Copilot]

Removed VS Code configuration directory in eee6d95.