Brings forward the node_reads_hit and nudb_bytes label corrections from phases 7
and 9.
Conflicts resolved keeping both sides:
- 06-implementation-phases.md: kept phase-10's unprefixed `storage_detail` gauge
name with phase-7's corrected getStoreSize() description.
- node-health.json: kept phase-10's rewritten panel structure and re-applied the
panel renames (NodeStore Read Found Ratio, NuDB Stored Bytes), legends and axis
labels on top of it.