Add AuthManager class to handle authentication with o11y iframe

What does this MR do and why?

This code is responsible for sending authentication messages to the o11y iframe and handling the response. It also handles retries and timeouts. It is broken out from Log a user into the O11y service react app (!197536 - merged) to help with review complexity.

Duo generated summary

This code adds a new authentication system for handling secure communication between web pages. The main addition is an AuthManager class that safely sends login credentials to embedded content (like iframes) from trusted websites.

The system includes several safety features: it automatically retries failed authentication attempts up to 3 times with increasing delays between attempts, validates that the embedded content is ready before sending credentials, and handles various error scenarios gracefully. It uses security tokens and unique identifiers to ensure messages are authentic and haven't been tampered with.

The authentication manager can notify other parts of the application when login succeeds or fails through callback functions. It also includes proper cleanup to prevent memory leaks by clearing timers when authentication completes.

References

Update login process to use observability_group_o11y_setting table

Screenshots or screen recordings

No UI changes. See final functionality screen recording

How to set up and validate locally

See final functionality testing

MR acceptance checklist

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