Copilot review round 2.
The exemption compares the WHATWG-canonicalized `URL.hostname`, so it covers
alternate spellings of three loopback *addresses* rather than three input
strings: `127.1`, `2130706433`, `0x7f.0.0.1`, `[0:0:0:0:0:0:0:1]` and a
root-anchored `127.0.0.1.` all pass. The behavior is right — the security
argument is about the address the request reaches, and all of these are the
loopback interface — but the comment described it as a literal-input match,
which it is not. It now states the contract, and six regression cases pin the
aliases alongside the existing near-miss cases.
This is also still an exact match for the SDK: `assertSecureTokenEndpoint` tests
`url.hostname` against the same three values after the same `new URL`
canonicalization, so an alias accepted here is one the SDK accepts too.
Separately, the smoke guide's fixture recipe left the shell in `clients/web`
after the build line, so the repo-root-relative paths on the next line resolved
under `clients/web` and the copy-pasted setup failed before the server started.
The build now runs in a subshell, and the block notes that the server announces
its URL on stderr and walks past a taken port.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GfHQ8vMm5NBgzbUJ6UwxmB
Signed-off-by: cliffhall <cliff@futurescale.com>