TestWLEDSchemeInference in test_devices_routes covers the POST/PUT
create-and-update flow with a stubbed WLED provider so the
infer_http_scheme integration hop has end-to-end coverage instead of
just the unit tests.
test_url_scheme grows public IPv6 (Cloudflare / Google / Quad9 DNS),
bracketed-form, and ULA cases. Adds an explicit pin for the Python
ipaddress documentation-prefix quirk (2001:db8::/32 is is_private,
so it routes to http:// even though some audits colloquially call it
"public").
alexei.dolgolyov
907bdaf043