fix(cli-smoke): add missing count() mock method (Issue #596)

The mock store in cli-smoke.mjs was missing the async count()
method that the real store interface provides. This caused the
assertion at line ~316 to fail with undefined !== 1 when
recallResult.details.count was accessed.

This is a pre-existing issue introduced by the lifecycle-aware
memory decay commit, not related to PR #516.

Author: jlin53882

test/cli-smoke.mjs

@@ -300,6 +300,7 @@ async function runCliSmoke() {
     },
     store: {
       async patchMetadata() {},
+      async count() { return 1; },
     },
     scopeManager: {
       getAccessibleScopes() {