Retire the runtime-tools edge and admit the wfcompile edges in the architecture baseline

Why: Q3 WP1/WP2 moved workflow execution out of runtime (workflow_script.go
deleted, so runtime no longer imports internal/tools) into the new
internal/wfcompile package, which legitimately depends on internal/tools
(script host) and internal/workflow (render/validate/Launch data layer).

Evidence: make test-boundaries green after the baseline update (77 edges,
negative test ok); the lint itself flagged both the stale edge and the new
ones (SELF).

Impact: baseline -1 edge (backend/runtime backend/tools), +3 edges
(backend/runtime backend/wfcompile, backend/wfcompile backend/tools,
backend/wfcompile backend/workflow).

Refs: Q3 plan WP1/WP2; task card .task/feature-agent-stack-q3.md

policy/architecture-baseline.json

@@ -52,7 +52,7 @@
   "backend/runtime backend/prompts",
   "backend/runtime backend/quality",
   "backend/runtime backend/squadadapter",
-  "backend/runtime backend/tools",
+  "backend/runtime backend/wfcompile",
   "backend/runtime backend/workflow",
   "backend/server backend/cardsvc",
   "backend/server backend/cmdbus",
@@ -72,6 +72,8 @@
   "backend/squadadapter backend/quality",
   "backend/store backend/blobstore",
   "backend/tools backend/quality",
+  "backend/wfcompile backend/tools",
+  "backend/wfcompile backend/workflow",
   "frontend/app frontend/components",
   "frontend/components frontend/app"
 ]