First tranche of the ~300-site raw SQL port. Metrics: node/service/
instance rows via generated queries; aggregation moved off TimescaleDB's
time_bucket onto portable date_bin (PG14+); interval uptime returns epoch
seconds; per-container writes dropped (container_metrics FKs a different
model — collector shape never matched). Domains: all reads/writes through
sqlcdb including the create transaction via WithTx; default-domain and
services.domain invariants unchanged. Both paths covered by live
Postgres tests gated on METRICS_TEST_DSN.
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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
