~anthropic/claude-sonnet-latest → B (6:4)

B fixes a real production bug (hardcoded hostnames breaking OAuth redirects across multiple providers) with a consolidated get-base-url utility applied consistently across 7 files, plus deploy workflow correction—broader, more impactful, and better factored. A is a solid test-infra fix (regex split bug, error handling, selector correctness) but is scoped narrowly to test mocks rather than production code paths.