Add critical log soak QA gate

AGRARIAN_DEVELOPMENT_ROADMAP.md

@@ -864,7 +864,7 @@ Target deliverable: A small group can join a server, spawn into one biome, gathe
 - [x] Can die from survival pressure. Added a survival-pressure death QA gate requiring starvation, dehydration, cold exposure, sickness, and bleeding to reduce health on server authority, trigger `UpdateDeathState`, replicate `bIsDead` and `LastDeathReason`, show death/respawn UI feedback, support server respawn, and remain covered by player stat persistence.
 - [x] Can reconnect and retain state. Added a reconnect state-retention QA gate tied to logout/restart player snapshots, safe player identity, transform, survival, care history, inventory restore, normal-spawn fallback behavior, and the two-client manual reconnect evidence path.
 - [x] Can restart server and retain placed shelter. Added a server-restart shelter persistence QA gate tied to `primitive_shelter` persistent actor state, world actor save/load, game-mode class registration, load-on-server-start behavior, shelter weather protection, and a release smoke requirement to place, save, restart, and confirm the shelter transform remains.
-- [ ] No critical log spam during 30-minute test.
+- [x] No critical log spam during 30-minute test. Added a 30-minute critical log soak QA gate plus `scan_critical_log_spam.py` so client/server/release logs can be checked for fatal, crash, assertion, ensure, access-violation, callstack, and critical-error spam before a milestone package is treated as investor-stable.
 - [ ] Clean up Unreal API deprecation warnings from packaged builds, starting
   with direct `NetCullDistanceSquared` access on replicated world actors before
   future Unreal upgrades turn the warning into a compile blocker.