Evaluate possible .NET Aspire binding context from VS

[mattchenderson]

There's an exploration underway around a binding context in the VS template engine which signals that the template is being added within an Aspire context.

The scenario for this is to tailor our templates to Aspire. Specifically, for item templates, it may make sense to include Aspire integration packages based on this context binding. There may also be some tailoring we'd like to do to the project template, but the scope of that is not yet defined.

Notably this is VS-specific, which may impact its feasibility for use. We should also assess what it would look like if we could get something more standardized at the SDK level.

I can provide details of the new binding context privately.