test(19.7-05): framework unit tests for every validation row and the gate's admin stage

- pier: TestCatalog, TestDispatch, TestGuardRules, TestSessions (Redis
  across two instances and the memory store), TestFanOut; the store clock
  and stateless-server seams in export_test.go
- surf: TestStreamingRoute (throttle, CORS profile and access-log pattern on
  a stream route) and TestPierMount in both builds; the streaming smoke
  restores the mount hook it replaces
- wristband TestMCPScopes; cabana TestAccountContributions (Postgres part:
  transaction and unchanged My account payloads), TestRecordActionPrompt,
  TestScopeLimitForMethods; TestRecordActionPromptRun pins the empty Value
  of an action without a prompt
- vitest: 403 and failed-load cases for My account contributions, the
  cancelled prompt
- gate: every name required (tagged runs included), account.go unchanged
  since 51d088a, admin stage live

modules/surf/streaming_smoke_test.go

@@ -88,7 +88,8 @@ func TestStreamingRouteSmoke(t *testing.T) {
 		}
 		return nil
 	}
-	defer func() { mountPier = nil }()
+	prev := mountPier
+	defer func() { mountPier = prev }()
 
 	app := transportApp(t, "development", map[string]string{
 		"http.yaml": transportBodyLimits,