test: replace create authority source pin

docs/reviews/2026-08-18-r3-test-truth-ledger.md

@@ -1498,3 +1498,43 @@ Verification follows the proportionate R3 policy:
 - a targeted scan finds source reads only in the two explicitly retained
   whole-tree policy methods. The final inventory and twelve-assembly Release
   gate remain deferred to closeout.
+
+## Batch AF create-authority drift-model contract replacement
+
+Batch AF converts the final approved test-model/source correspondence check.
+`CreateAuthorityDriftModelSourcePinTests` is renamed to
+`CreateAuthorityDriftModelContractTests`; its descriptive test method
+`HandCalledDriftProbe_StillModelsTheExecutorDrainAdvance` is retained. No
+product source changes and no test is removed.
+
+The replacement no longer regexes two Runtime files. It inspects compiled
+Runtime metadata and proves:
+
+- `ApplyWeenieDescriptionAction` applies the accepted description, refreshes
+  the canonical snapshot, advances create authority exactly once, and then
+  advances the executor baseline in semantic execution order;
+- `RegisterEntityCore` still has the named Boolean initial-residence input,
+  refreshes the ordinary existing-generation snapshot, and places the one
+  registration-time authority advance behind a conditional branch that skips
+  over the call; and
+- the Runtime assembly contains exactly those two call sites targeting
+  `RuntimeEntityDirectory.AdvanceCreateAuthority`: the modeled executor drain
+  and the gated ordinary registration route.
+
+This is the stale-model alarm the source regex intended, but it now survives
+comments, whitespace, local renames, and equivalent expression refactors.
+The expectation-item 6/8 probe comments in the hydration and supersession
+suites now say `metadata-pinned` and name the new contract class, preserving
+the rationale without leaving misleading source-pin references.
+
+Verification follows the proportionate R3 policy:
+
+- the contract plus its hydration and supersession behavior suites pass 90/90;
+- the complete `AcDream.App.Tests` hermetic lane passes 5,381/5,381 with zero
+  skips or failures;
+- the complete locked Release build covers all 44 projects with zero warnings
+  and zero errors; and
+- targeted scans find no source reader in the renamed contract and no stale
+  source-pin comment in the affected tests. With this batch, all 85 approved
+  replacements are implemented; final inventory reconciliation and the one
+  complete Release gate follow next.