Adds pt-... token auth as an alternative to OAuth device flow. A PAT can't
sign COSY requests directly, so it's exchanged for a short-lived job token
(jt-...) plus userId via openapi.qoder.sh, then used for signing.
Also fixes job-token traffic (jt-...) being rejected by api3.qoder.sh with
403 "Login expired" — the official qodercli serves jt- traffic from
api2.qoder.sh instead, so buildUrl/model-list routing now branches on it.
Quota usage and the dashboard add-key modal are updated to resolve PAT
credentials and label the field correctly, and bulk-add now validates
each key so it gets a real testStatus instead of a hardcoded "unknown".