Initial starterkit creation

[robearlam]

This is the initial commit of code for the XM Cloud ASP.NET Core Starter Kit. Some notes about it's contents:

• This is a replica of the new structure that has been approved for the Next.js starter kit (foundation head).
• The repo favours a FED-First development approach as per the new direction for XM Cloud. The container based approach is still included here, and it's assets can be found in the local-containers folder.
• The components included are a direct port of the same components found in the Next.js starter, replicating the logic and generated markup/css.
• There are currently 2 components that haven't been ported over as we're blocked waiting for changes to the ASP.NET Core SDK (Navigation and FEaaS). Both of these are called out in the main README to ensure readers are aware.
• The main README contains initial steps to run the repo locally against an XMC preview endpoint, using VS Dev Tunnels to connect Pages to the local developer machine. Work will need to be done to refine this process in the future but this will do for an initial beta release, so we can garner initial feedback.
• This is currently using the "old" method of connecting to the XMC Preview and Edge endpoints, it needs updating to support the ContextID approach, but this is blocked until the SDK is supports this approach.

[robearlam]

@sc-ivanlieckens - Fixed up most of your comments and marked those as Resolved.

Added comments to the others that are still open above.

[sc-ivanlieckens]

How do we feel about https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-10.0/file-scoped-namespaces ?

[robearlam]

How do we feel about https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-10.0/file-scoped-namespaces ?

I hadn't seen this feature was introduced, reducing indentation where possible is always good in my book. Implemented.