f62f35e24 restored the v5 used | cache | free memory split for Proxmox
nodes and guests, but standalone host agents still reported a flat
used/free pair, so the Machines page memory bar could not show the
reclaimable segment. Flagged by the Machines page v5 parity audit.
- Host agent reports cacheBytes (gopsutil Available minus Free); the
ZFS ARC adjustment recomputes free so used + cache + free still
covers the total.
- ApplyHostReport maps the field into models.Memory.Cache and clamps
inconsistent or older-agent reports so used + cache never exceeds
total.
- AgentMemoryMeta carries cache onto unified resources so the frontend
agent payload exposes it.
- Mock generic hosts split a third of non-used pages as cache, and the
node-linked host conversion now holds the invariant instead of
stacking the node's cache on top of a recomputed free.
- Contracts: monitoring, unified-resources, and storage-recovery now
document the split (also covering the f62f35e24 node/guest surface,
which landed without contract deltas).
ff5a0b4957