Xcode CAS daemon respects the runner’s override cache endpoint and feature flags

The runner-supplied private-network cache override is now forwarded into the Xcode compilation cache (CAS) daemon’s launchd-agent environment in addition to TUIST_TOKEN. Previously the module cache used the dispatch override while the CAS resolved the public endpoint, leaving the Xcode cache net-negative on a full compile on runner machines. Combined with #11481 (feature flags), the daemon now resolves cache endpoints the same way the rest of the CLI does.