fix: AuthFetch should fallback to non auth call when initial handshake return non ok http status

[dorzepowski]

No description provided.

[Copilot]

Pull Request Overview

This PR fixes the AuthFetch functionality to properly fallback to non-authenticated HTTP calls when the initial authentication handshake fails with a non-OK HTTP status. The change replaces string-based error checking with proper error type checking.

• Introduces a new error type ErrHTTPServerFailedToAuthenticate for standardized error handling
• Updates the authentication error return to use errors.Join() with the new error type
• Replaces string-based error detection with proper errors.Is() checking

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
auth/transports/errors.go	Adds new error type ErrHTTPServerFailedToAuthenticate for authentication failures
auth/transports/simplified_http_transport.go	Updates error return to include the new error type using errors.Join()
auth/clients/authhttp/authhttp.go	Replaces string-based error checking with proper errors.Is() type checking

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
auth/clients/authhttp/authhttp.go	0.00%	1 Missing ⚠️
auth/transports/simplified_http_transport.go	0.00%	1 Missing ⚠️

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[rohenaz]

lgtm