Add Azure Site Extension bundle elements to agent

[mrickard]

Description

The Node Agent should be installable as an App Service Extension for Azure. Site Extensions are published to NuGet in a particular format, which is demonstrated by the Java Agent's site extension repository.

See the notes in Confluence: https://newrelic.atlassian.net/wiki/spaces/INST/pages/3556245543/ANNS+-+APM+language+support#InScope

Acceptance Criteria

This issue is focused on adding the site extension assets to the Node Agent repo. If the directory and document structure are created correctly, we should be able to follow a process similar to the Java agent to create a site extension locally, and to upload it to a personal NuGet account for testing. (That's similar to the testing method used by the .NET team.)

When installed in a simple web app, we should be able to see telemetry in NR One staging.

Dependencies

Required by #2441

[workato-integration]

https://new-relic.atlassian.net/browse/NR-300195