boto3 and azure-identity freeze the credential chain into the client at
construction, and the process env under a multiplexed turn belongs to the launch
profile. A region-only (bedrock) / config-only (lru_cache) slot therefore signed a
served profile's calls with the launch profile's keys and served its account's
model list to everyone.
Under a HERMES_HOME override the clients are built from the profile's secret
scope (AWS_* / AZURE_* from its .env) and cached per (home, service, region) /
(home, config); the discovery cache key carries the home. The unscoped path keeps
the region slot and the maxsize=1 lru byte-for-byte.
Teknium