SampleSandboxMetrics previously filtered WHERE status IN ('running',
'starting', 'paused'), which returned no rows when all capsules were
stopped. This caused zero snapshots to be skipped, leaving the
time-series charts with no trailing data points instead of showing
the expected zero values.
Remove the WHERE filter so the query groups by all teams that have
any sandbox row. The per-status FILTER clauses on the aggregates
already produce correct zero counts for stopped capsules.
Also includes the per-VM RAM ceiling formula change (sum(ceil(each/2))
instead of ceil(sum/2)).