Preset system: ResolvePolicy resolves named presets (database, general,
throughput) with per-field overrides into concrete volume parameters.
Create path now uses resolved policy instead of ad-hoc validation.
New /block/volume/resolve diagnostic endpoint for dry-run resolution.
Review fix 1 (MED): HasNVMeCapableServer now derives NVMe capability
from server-level heartbeat attribute (block_nvme_addr proto field)
instead of scanning volume entries. Fixes false "no NVMe" warning on
fresh clusters with NVMe-capable servers but no volumes yet.
Review fix 2 (LOW): /block/volume/resolve no longer proxied to leader —
read-only diagnostic endpoint can be served by any master.
Engine fix: ReadLBA retry loop closes stale dirty-map race when WAL
entry is recycled between lookup and read.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
