Add visitor phone lookup flow

server/internal/httpapi/limiter_test.go

@@ -0,0 +1,26 @@
+package httpapi
+
+import (
+	"testing"
+	"time"
+)
+
+func TestQueryLimiterResetsAfterWindow(t *testing.T) {
+	now := time.Unix(100, 0)
+	limiter := newQueryLimiter(func() time.Time { return now }, 2, time.Minute)
+
+	if allowed, _ := limiter.allow("phone:test"); !allowed {
+		t.Fatal("first query should be allowed")
+	}
+	if allowed, _ := limiter.allow("phone:test"); !allowed {
+		t.Fatal("second query should be allowed")
+	}
+	if allowed, retry := limiter.allow("phone:test"); allowed || retry <= 0 {
+		t.Fatalf("third query should be limited with a retry duration, got allowed=%v retry=%s", allowed, retry)
+	}
+
+	now = now.Add(time.Minute)
+	if allowed, _ := limiter.allow("phone:test"); !allowed {
+		t.Fatal("query should be allowed after the window resets")
+	}
+}