Add .NET 9.0 Support

[GeekInTheNorth]

Closes #264

[Copilot]

Pull Request Overview

This pull request updates the project to support .NET 9.0 by renaming namespaces from "OptimizelyTwelveTest" to "OptiNetNine" and updating the CI workflow to build and test multiple .NET versions.

• Updated all namespaces to reflect the new .NET 9.0 support
• Enhanced the GitHub workflow to include build and test steps for .NET 6.0 and .NET 9.0
• Adjusted branch filters for push and pull_request triggers in the workflow

Reviewed Changes

Copilot reviewed 150 out of 151 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
Sample/OptiNetNine/Features/GeneralContent/GeneralContentPageViewComponent.cs	Updated namespace from OptimizelyTwelveTest to OptiNetNine
Sample/OptiNetNine/Features/GeneralContent/GeneralContentPageController.cs	Updated namespace and using statements
Sample/OptiNetNine/Features/GeneralContent/GeneralContentPage.cs	Updated namespace
Sample/OptiNetNine/Features/Common/UpperCaseNamingPolicy.cs	Updated namespace
Sample/OptiNetNine/Features/Common/Pages/SitePageData.cs	Updated namespace
Sample/OptiNetNine/Features/Common/Pages/ISitePageViewModel.cs	Updated namespace
Sample/OptiNetNine/Features/Common/Pages/ISitePageData.cs	Updated namespace
Sample/OptiNetNine/Features/Common/PageControllerBase.cs	Updated namespace
Sample/OptiNetNine/Features/Common/Media/ImageContentViewComponent.cs	Updated namespace
Sample/OptiNetNine/Features/Common/Media/ImageContent.cs	Updated namespace
Sample/OptiNetNine/Features/Common/GroupNames.cs	Updated namespace
Sample/OptiNetNine/Features/Blocks/RichText/RichTextViewComponent.cs	Updated namespace
Sample/OptiNetNine/Features/Blocks/RichText/RichTextBlock.cs	Updated namespace
Sample/OptiNetNine/Features/Blocks/Embed/EmbedBlockViewModel.cs	Updated namespace
Sample/OptiNetNine/Features/Blocks/Embed/EmbedBlockViewComponent.cs	Updated namespace
Sample/OptiNetNine/Features/Blocks/Embed/EmbedBlock.cs	Updated namespace
Sample/OptiNetNine/Features/API/TestApiController.cs	Updated namespace
.github/workflows/dotnet.yml	Updated workflow configuration to use .NET 9.0 and added steps for .NET 6.0

Files not reviewed (1)

• Sample/OptiNetNine.sln: Language not supported

Comments suppressed due to low confidence (2)

.github/workflows/dotnet.yml:5

• The change in the push trigger branch filter restricts runs to feature branches only, which may unintentionally exclude commits pushed directly to main or develop. Please confirm if this change was intended.

branches: [ "feature/**" ]

.github/workflows/dotnet.yml:20

• The inclusion of restore/build/test steps for .NET 6.0 in a PR focused on .NET 9.0 support might be unintended; please verify if maintaining support for .NET 6.0 is required.

run: dotnet restore Sample/OptiNetSix.sln