Since real device names started reaching the header, an accented one
made login impossible: dart:io refuses header values above 0x7F, and
CFNetwork puts the raw code unit on the wire as a Latin-1 byte, which
Kestrel rejects as a malformed request with 400 before Jellyfin routes
POST /Users/AuthenticateByName.
Encode every field the way the official Jellyfin SDK does; the server
already reverses it with WebUtility.UrlDecode, so the wire value stays
pure ASCII while the device list shows the real name. Quotes, commas
and `=` no longer need stripping either. sanitizeHeaderValue, which
still guards the Plex headers, now folds Latin letters to their base
form instead of emitting bytes no transport accepts.
close#1685
edde746
53535e1678