chore: add server-changes for pr05

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: d-cs

.server-changes/run-ops-split-webapp-foundation.md

@@ -0,0 +1,6 @@
+---
+area: webapp
+type: feature
+---
+
+Add the webapp foundation for the run-ops database split: topology/flag wiring, split-mode gating, a distinct-DB boot sentinel, and control-plane resolver read-through (all inert until `RUN_OPS_SPLIT_ENABLED`).