chore: merge main into e2e prerequisites

.github/workflows/e2e-replication-nightly.yml

@@ -40,7 +40,7 @@ on:
   schedule:
     # 04:00 UTC nightly — staggered clear of fuzz/e2e-s3tests (02:00),
     # stale (01:30) and performance-ab (06:00).
-    - cron: "0 4 * * *"
+    - cron: "29 4 * * *"
 
 # Only alert-on-failure needs more than read access; it declares its own
 # job-level `issues: write`.
@@ -192,6 +192,9 @@ jobs:
           cache-save-if: 'false'
           install-build-packaging-tools: 'false'
 
+      - name: Verify protocol socket oracle
+        run: ss -tn state CLOSE-WAIT >/dev/null
+
       # The suite owns fixed protocol ports and serializes its internal cases.
       - name: Verify protocol e2e membership
         env: