Complete WP-0003 T06 pilot validation and sync credential routing docs

Close the dangling MVP pilots task with H1 provider-switch test, pilot
validation report, and resolver tenant-override fix. Add credential routing
guidance to AGENTS.md and Claude rules.

tests/test_registry_resolver.py

@@ -69,6 +69,7 @@ def test_resolver_precedence_and_decision():
             owner="o",
             default_value=True,
             safe_fallback=False,
+            expected_lifetime="long_lived",
         )
     )
     reg.register(
@@ -78,6 +79,7 @@ def test_resolver_precedence_and_decision():
             "...",
             owner="o",
             default_value=False,
+            expected_lifetime="long_lived",
         )
     )
 
@@ -87,7 +89,7 @@ def test_resolver_precedence_and_decision():
             "tenant:acme:tenant.test": True,
         }
     )
-    resolver = Resolver(reg, provider.values)
+    resolver = Resolver(reg, provider._values)
 
     # Kill wins
     d = resolver.evaluate("kill.test", True, {"tenant_id": "acme"})