Generalises #37747. The WS Origin guard (_ws_host_origin_is_allowed) only
trusted the packaged Electron app's non-web origin (file:// / null / app://)
when the bind was NOT OAuth-gated. The packaged Hermes Desktop renderer loads
over file://, so when it drives a remote OAuth-gated gateway its /api/ws
upgrade was rejected with HTTP 403 even though _ws_auth_ok had already
validated the single-use ?ticket= one line earlier.
This guard runs only AFTER _ws_auth_ok has accepted the WS credential, which
is the real auth boundary in every mode:
* loopback bind -> legacy dashboard session token
* non-loopback --insecure -> legacy session token (Tailscale / LAN, #37747)
* OAuth-gated public bind -> single-use, 30s-TTL, identity-bound ?ticket=
A non-web origin can only come from a native client; a DNS-rebinding attack
always arrives from an http(s) origin and is still match-checked against the
bound host. So once the upstream credential check has passed, the Origin guard
adds nothing for a non-web origin. Collapsed the loopback/non-gated special
cases to 'return True' for non-web origins.
http(s) origins keep the strict same-host check, so browser DNS-rebinding
defence is unchanged.
Tests: gated file:///null/app:// now asserted ALLOWED; cross-site http(s)
still rejected on gated and loopback binds; #37747's loopback and
non-loopback-insecure cases retained. 37/37 test_dashboard_auth_ws_auth +
test_web_server_host_header pass.