fix: refresh VM status watch on every tick

[CMGS]

Summary

• Redraw vm status --watch on each tick or metadata event even when the VM record is unchanged, so live THROTTLED counters and the header time advance.
• Reuse VM state reconciliation without building an unused snapshot.
• Cover an unchanged running VM whose cpu.stat throttling counters increase between ticks.

Validation

• GOWORK=off make fmt-check
• GOWORK=off make lint (linux and darwin: 0 issues)
• GOWORK=off asl -forwarder=false ./...
• GOWORK=off GOOS=linux asl -forwarder=false ./...
• GOWORK=off go test -race -count=1 ./...