Connectors with real connection tests

The Entra connector provisions everything automatically. Every service connector must pass a real connection test before it can be enabled.

• Automatic Entra provisioning: application, certificate, admin consent
• Read-only Graph permissions only — every scope is .Read.All
• Exchange and Purview reuse the Entra certificate — zero extra setup
• Test connection on all seven service connectors
• Failed test = connector disabled and locked until a test passes
• Access errors name the exact missing Graph permission