SLC discoveryability Logic

[gladjohn]

Following are the options for SLC endpoint discovery

• Try SLC endpoint, and fallback to GetToken endpoint (preferred)
• New API for exclusive SLC experience (cut)
• Add SLC supported sources (cut)
• environment variables for feature detection (cut)

[gladjohn]

Final logic to determine SLC is based on machine key availability. Machine key to be setup by provisioning agent