Upgrade to .NET 8

[Copilot]

Azure Functions no longer supports .NET 6. This upgrades the function app and test projects to .NET 8.0, resolving the CI deployment error about unsupported dotnet language versions.

Changes

• Updated TargetFramework from net6.0 to net8.0 in:
  • FunctionApp/FunctionApp.csproj (Azure Functions v4)
  • UnitTest/UnitTest.csproj
  • StravaApiTest/StravaApiTest.csproj
  • CosmosStorageTest/CosmosStorageTest.csproj
• Updated .github/workflows/equipper-test.yml to use .NET 8.0.x

Library projects (Api, StravaApi, CosmosStorage) remain on netstandard 2.0/2.1 for compatibility.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Update to dotnet 8</issue_title>
<issue_description>dotnet 8 is the latest support dotnet version for function apps. Equipper hasn't been updated in years so it is still on version 6. Please update to version 8. The following error should no longer happen in CI:

The function language version detected is unsupported or invalid. The following dotnet language versions are valid: 8.0. If you are not using Azure Functions, you can skip this check by removing the 'api_location' input from the workflow file.</issue_description>

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

• Fixes Update to dotnet 8 #65

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[github-actions]

Azure Static Web Apps: Your stage site is ready! Visit it here: https://kind-ocean-0a357fa0f-66.eastus2.azurestaticapps.net