Архитектура: вынести exact-route protection arbitration в assistantRoutePolicy и защитить address lane от ложного deep fallback

docs/ARCH/11 - architecture_turnaround/11 - continuity_stabilization_plan_2026-04-17.md

@@ -486,6 +486,19 @@ Still open after the accepted phase12 replay:
   - this matters because `address vs deep` arbitration is one of the last heavy control-plane seams in the project: it decides whether the assistant stays in exact-data mode or escalates into deep-analysis mode, and leaving that logic as a long inline branch makes future domain expansion much more likely to reintroduce contradictory fallback rules;
   - the move does not change the route owner, but it makes the owner explicit and testable as one decision unit inside route policy rather than a fragile chain of local booleans;
   - targeted route/continuity/transition suites remain green after the move, and a fresh live rerun of `address_truth_harness_phase12_wider_saved_session_pool` on `2026-04-19` remains accepted `20/20`, which is the proof that the flagship mixed contour survives the extraction of the deep fallback arbitration seam.
+- the next route-arbitration pass now extracts the protected exact-route contract from another dense inline branch:
+  - `assistantRoutePolicy` now owns `resolveAddressLaneProtectionArbitration(...)`, so the following coupled verdicts are produced by one explicit helper instead of a scattered cluster of route-local booleans:
+    - `supportedAddressIntentDetected`
+    - `supportedAddressRouteCandidateDetected`
+    - `semanticDeepInvestigationHintDetected`
+    - `semanticAggregateShapeDetected`
+    - `followupSemanticOverrideToDeepAllowed`
+    - `exactAddressIntentProtectedFromSemanticDeepHint`
+    - `protectAddressLaneFromFallback`
+  - this matters because the exact-route protection contract is what stops a valid address route from being pulled into deep-analysis mode just because semantic guards or hybrid prompts hint at deeper investigation;
+  - keeping that contract in one helper reduces another major chance that future domain expansion introduces contradictory exact-route vs deep-fallback precedence in nearby branches;
+  - targeted route/continuity/transition suites remain green after the move, including direct regression coverage that an exact VAT route must stay in the address lane even when only a semantic deep hint is present;
+  - a fresh live rerun of `address_truth_harness_phase12_wider_saved_session_pool` on `2026-04-19` remains accepted `20/20`, which is the proof that the flagship mixed contour still survives after extracting the route-protection seam.
 
 ## Next Execution Slice (2026-04-18)