Adds x-litellm-model-name, -call-id, -key-spend, -response-duration-ms, -overhead-duration-ms, -callback-duration-ms, -attempted-retries and -attempted-fallbacks to the CORS expose list, on the GM's go-ahead. Renames COST_HEADERS to EXPOSED_HEADERS since the list is no longer only costs. x-litellm-key-spend discloses the caller's own key spend, which is their own data; noted in the thread so it can be dropped if anyone objects.
start.sh hardcoded and exported LITELLM_CORS_ORIGINS, so the Cloudron app env that is meant to control it was silently overridden — the change I made earlier tonight looked applied and was inert. It now defaults only when unset, so the app env wins, and the co-op decision to allow all origins (co-op/support#38) actually takes effect. Comment rewritten for the current version and the reasoning. Also adds patch_expose_cost_headers.py (wired into the Dockerfile) so x-litellm-response-cost* can be read by cross-origin clients (co-op/support#39); upstream closed the request as stale, so it is handled at the app layer like the other patches.