Instrument DeliveryService (enqueue, fetch) and KeyService (key_package_upload, key_package_fetch) with storage latency histogram recording. Add periodic uptime gauge task (every 15s). Log effective rpc_timeout_secs, storage_timeout_secs, and webtransport_listen at startup to eliminate dead_code warnings on EffectiveConfig fields.
Rename all crate directories, package names, binary names, proto package/module paths, ALPN strings, env var prefixes, config filenames, mDNS service names, and plugin ABI symbols from quicproquo/qpq to quicprochat/qpc.
