Port PR from PBS-Java: Core: Improve traceability for Prebid Cache stores

[cross-repo-issue-creation]

A PR was merged over on PBS-Java

• Core: Improve traceability for Prebid Cache stores prebid-server-java#3757
• timestamp: 2025-02-20T10:33:30Z

[bretg]

PBS is creating the UUID to contain more useful information

• a host-level flag cache.append-trace-info-to-cache-id:true causes the addition account ID and datacenter to UUID
• datacenter comes from datacenter-region, but truncated to 4 chars. (we might remove dashes from the datacenter someday soon)
• Random UUID is generated and then replace the first portion of the UUID with account and datacenter. e.g.

ACCOUNT-DATACENTER-tailPortionOfUUID

(the code currently appends the head portion of the UUID, but we plan to change this to tail)

Metrics

We can now track details about the cache TTL at the global and per-account level

• prebid_cache.creative_ttl.{json,xml}.METER
• account.*.prebid_cache.creative_ttl.{json,xml}.METER - this is logged always, not constrained to basic or detailed verbosity.