Census approval: wake-latency-2

Ruling census-ruling-wake-latency-2. Every change below keeps the disposition it already has, so it needs an approval, not a decision.

| unit | change | read sites | what changed | |---|---|---|---| | internal/activator/backend_exec.go ExecBackend.spawnUnitFrom | body | unchanged (26) | times the launch's steps with time.Now() (build, prepare, launch file, gate, root start) and adds them to its existing "started" journal line; no read added or moved | | internal/activator/prepare.go ExecBackend.prepareAt | body | unchanged (1) | passes nil for prepareKeyedAt's new timing parameter; nothing else changed | | internal/activator/prepare.go ExecBackend.prepareKeyedAt | body | unchanged (13) | takes an optional timer and marks its steps with time.Now() (dirs, admin token, instance key, env, control socket, key gate, logs); no read added or moved | | internal/activator/swaphold.go Service.startPinnedAt | sites | +registry:Host | times record, staged start and health with time.Now() and logs them with rt.Host after a healthy start (the new registry:Host site is that log line); no read added or moved |

Envelopes re-pinned: internal/activator, internal/instancectl, internal/lease.

Seal: 0ca3baafa26f59c0b7d8c6d6a39237d074afb71f885b7fbd50debebab5bf89f2 → 27b020590845320cd37b94fdeddf61b7c6f90e12ba7841850f2e7bbd6836ecd8.

Overlay: internal/provision/testdata/plan14-root-reads-wake-latency-2.tsv, appended to internal/provision/testdata/plan14-root-reads-chain.tsv.