* feat(prometheus): configure deployment caller identity
* test(prometheus): satisfy strict caller identity lint
* fix(prometheus): align caller identity on latency metrics
* fix(prometheus): validate caller identity mode before collectors register
Fail config load on an invalid prometheus_deployment_and_latency_caller_identity
value (including null) and on include_labels entries the selected mode removes
from a target metric, instead of booting green with an empty /metrics.
Validate the mode at the top of PrometheusLogger.__init__ so an invalid value
raises before any collector lands in the process-global registry, keeping
retries free of duplicated-timeseries errors. Label-validation errors now name
the mode setting alongside the rejected label.
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Co-authored-by: Mark Philipp <mphilipp622@gmail.com>
Co-authored-by: Yucheng Zhu <yucheng@berri.ai>
