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…ead replica lags (#3910) ## Summary When the realtime runs feed (the backend behind the `realtimeBackend` feature flag) hydrates a change from a Postgres read replica, the read can race the replica's apply of the very write that triggered it. The delivered row then carries the previous change's content, and an isolated final change (for example a last `metadata.set` before a run goes quiet) is not corrected until the roughly 20 second backstop poll. Measured against a replica with deliberate apply delay, every delivery trailed exactly one change behind and a final change stranded for the full backstop interval. ## Fix Publishers stamp each change record with the committed row's `updatedAt`, taken from writes they already perform, so the stamp costs no extra queries. The router delays its wake hydrate until the replica's measured lag has passed, anchored to that timestamp: a record that has already spent longer than the lag in transit is hydrated immediately, so only the racing leading edge ever waits. After hydrating, a tripwire compares each row against its record's watermark. Still-stale rows are withheld and retried briefly, and each detection feeds the lag estimate. If retries run out, the rows are delivered anyway (liveness over freshness) and follow-up re-hydrates emit the fresh version through the normal working-set diff once the replica catches up, with the backstop as the terminal net. Replica lag is sampled reader-side only, and only while feeds are active. Aurora reports live lag via `aurora_replica_status()`; vanilla Postgres can only report "caught up or not" (mid-apply lag is not honestly measurable from a replica), so tripwire observations floor the estimate there. Deployments without a replica resolve to zero lag and skip the gate entirely. Tunables live under `REALTIME_BACKEND_NATIVE_REPLICA_LAG_*`, and `realtime_native.stale_hydrates` plus `realtime_native.replica_lag_estimate_ms` make replica health observable. Two adjacent fixes: a metadata update that writes nothing no longer publishes a change record, and buffered parent and root metadata operations now publish when the flusher writes them, so those changes wake live feeds instead of waiting for the backstop. For local testing, `docker-compose` gains an opt-in `database-replica` service (compose profile `replica`) with a configurable `recovery_min_apply_delay`, which reproduces replica-lag behavior deterministically. With the gate disabled this rig reproduces the one-change-behind delivery exactly; with it enabled, deliveries arrive with current content at roughly the true replica lag, across write rates faster and slower than the lag itself.
Refreshes the locked `shell-quote` to 1.8.4 (transitive, lockfile-only). <!-- This is an auto-generated description by cubic. --> <a href="https://cubic.dev/pr/triggerdotdev/trigger.dev/pull/3913?utm_source=github" target="_blank" rel="noopener noreferrer" data-no-image-dialog="true"><picture><source media="(prefers-color-scheme: dark)" srcset="https://www.cubic.dev/buttons/review-in-cubic-dark.svg"><source media="(prefers-color-scheme: light)" srcset="https://www.cubic.dev/buttons/review-in-cubic-light.svg"><img alt="Review in cubic" src="https://www.cubic.dev/buttons/review-in-cubic-dark.svg"></picture></a> <!-- End of auto-generated description by cubic. -->
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