feat: implement programmatic auth API

[mikecrab]

Implement promise based authenticateRequest() API that enables programmatic execution of Passport strategies

Key additions:

• Returns an explicit AuthResult object containing the resolution of the auth attempt
• Adds an AuthContext to capture and provide data for logging and metrics
• Maintains backwards compatibility with hook logic
• Includes demo-auth-server.ts to test the code

Testing
Demo server created

Calling the route with the invalid Api Key before logging in to get a session cookie results in both strategies failing

Calling the route with the valid API Key before logging in to get a session cookie results in the session key failing, then the API key authentication succeeding

If we then hit the login route

We now have a cookie with a valid session so if we attempt authentication with the valid or invalid key, authentication will pass since it attempts to use session before even using the API keys

If we then logout, our session will be cleared and we can see that we will fall back to the API key auth again and we get the original results above