feat: migrate m3 deprecated timers to histograms

[thijmv]

Summary

This PR migrates all timers used in Kraken to histograms, as timers are slowly being deprecated by M3. Timers not used in any dashboard panel or alert are dropped instead.

Metrics

The bucket ranges for the metrics are based on seven days of production data.

Metric	Range	Reason
lib/middleware:latency	1ms-8.7m (n=20)	Tracker 50ms p95, proxy 500s p99.9, agent alert 2m/5m, proxy alert 10s/20s
origin/blobserver:replicate_blob	10ms-21.8m (n=18)	Fast zones 50ms p50, regular 5-10m spikes, 21m outliers
proxy/proxyserver:blob_download_time	1ms-8.7m (n=20)	5ms p1, avg 0.4-1.7s p95, alert 2m/5m

The following metrics were dropped, as they were not used in any panel or alert:

• tracker/trackerserver:get_metainfo
• lib/persistedretry/tagreplication:replicate
• lib/persistedretry/tagreplication:lifetime

Future work

• Update queries for dashboard panels and alerts.
• Validate appropriate histogram bucket distribution.