Add Publish to NuGet step. #468

	name: Build & Test

	on:
	push:
	branches: ["main"]
	pull_request:
	branches: ["main"]
	release:
	types: ["published"]

	jobs:
	Windows:
	runs-on: windows-latest

	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0 # avoid shallow clone so nbgv can do its work.
	- name: Setup .NET
	uses: actions/setup-dotnet@v4
	with:
	dotnet-version: 9.0.x
	- name: Build & Test
	run: make
	- name: Upload artifacts
	if: github.ref == 'refs/heads/main'
	uses: actions/upload-artifact@v4
	with:
	name: build-artifacts
	path: artifacts/
	- name: Upload to Codecov
	uses: codecov/codecov-action@v5
	with:
	files: artifacts//.cobertura.xml
	token: ${{ secrets.CODECOV_TOKEN }}
	- name: Publish packages to Feedz.io
	if: github.event_name == 'push'
	run: make push NUGET_SOURCE=https://f.feedz.io/eiriktsarpalis/polytype/nuget/index.json NUGET_API_KEY={{ secrets.FEEDZ_IO_KEY }}
	- name: Publish packages to NuGet
	if: github.event_name == 'release'
	run: make push NUGET_SOURCE=https://api.nuget.org/v3/index.json NUGET_API_KEY=${{ secrets.NUGET_API_KEY }}

	Linux:
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0 # avoid shallow clone so nbgv can do its work.
	- name: Setup .NET
	uses: actions/setup-dotnet@v4
	with:
	dotnet-version: 9.0.x
	- name: Build & Test
	run: make

	MacOS:
	runs-on: macos-latest

	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0 # avoid shallow clone so nbgv can do its work.
	- name: Setup .NET
	uses: actions/setup-dotnet@v4
	with:
	dotnet-version: 9.0.x
	- name: Build & Test
	run: make

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