fix(statusserver): improve bearer token parsing and add helper tests

[suchirkolli]

Summary

This PR adds focused unit tests for helper functions in pkg/statusserver:

• extractRawToken
• TokenAudience
• StatusUrl

It also makes bearer token parsing in extractRawToken more robust by:

• handling repeated whitespace with strings.Fields
• accepting case-insensitive Bearer with strings.EqualFold

Why

These helpers are small but important for status server auth and path generation. Adding direct unit test coverage makes the behavior clearer and improves reliability for future changes.

Changes

• add table-driven tests for extractRawToken
• add table-driven tests for TokenAudience
• add table-driven tests for StatusUrl
• update extractRawToken to handle extra whitespace and lowercase bearer

Fixes #3404

[google-oss-prow]

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[Copilot]

Pull request overview

This PR adds focused unit tests for helper functions in the status server package and improves the robustness of bearer token parsing. The changes include new table-driven tests for extractRawToken, TokenAudience, and StatusUrl functions. The extractRawToken function is enhanced to handle extra whitespace using strings.Fields() and to accept case-insensitive Bearer prefix using strings.EqualFold(), making the authentication header parsing more resilient to common variations in formatting.

Changes:

• Add comprehensive table-driven tests for extractRawToken with 8 test cases covering valid tokens, empty headers, missing tokens, wrong schemes, multiple spaces, and case variations
• Add table-driven tests for TokenAudience function with multiple namespace and job name combinations
• Add table-driven tests for StatusUrl function with multiple namespace and job name combinations
• Improve extractRawToken to handle repeated whitespace and case-insensitive Bearer prefix

Reviewed changes

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

File	Description
pkg/statusserver/auth.go	Updated extractRawToken to use strings.Fields() and strings.EqualFold() for more robust bearer token parsing
pkg/statusserver/auth_test.go	New comprehensive table-driven tests for extractRawToken covering valid tokens, edge cases, and new behavior
pkg/statusserver/utils_test.go	New table-driven tests for TokenAudience and StatusUrl helper functions

[suchirkolli]

Hi, I’m applying to GSoC and started contributing to Kubeflow Trainer with this change. I’d appreciate any feedback when you have time.