The backend-lifecycle harness asserted a literal — "is already in use, so the
backend could not" — while its own comment said the point was "the exact
phrasing BootstrapSplash.detectHints localizes". Those are not the same thing,
and the gap showed: rewording the message by who actually holds the port kept
the matcher firing and still failed the test.
It now asserts the real contract, the same one the Rust unit tests pin: the
message mentions a port, says it is in use after that, and names the port
number. Any wording that satisfies detectHints satisfies this; any that does
not, fails — which is the failure worth catching, because it silently costs
the user the localised hint.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017ypcgSsh5j2PEonSJiAU1S
