feat: add gallery pagination, dynamic progress colors, and UX fixes

- Replace infinite scroll with page-based navigation in gallery
- Add dynamic progress color (blue→amber→red) in encyclopedia
- Fix timeline not returning to realtime when closing in archive mode
- Simplify image detail modal close button styling
- Add web-design-reviewer skill

src/components/cloud/ImageDetailModal.vue

@@ -187,7 +187,7 @@ onBeforeUnmount(() => {
           <button
             type="button"
             @click="close"
-            class="image-detail-close-button absolute right-4 top-4 z-30 flex h-10 min-h-10 w-10 min-w-10 max-w-10 appearance-none items-center justify-center overflow-hidden border border-white/30 bg-white/15 p-0 text-white shadow-lg backdrop-blur-md transition-colors hover:bg-white/25"
+            class="image-detail-close-button absolute right-4 top-4 z-30 flex h-10 min-h-10 w-10 min-w-10 max-w-10 appearance-none items-center justify-center overflow-hidden border-0 bg-transparent p-0 text-white/70 shadow-none transition-colors hover:text-white [&_svg]:stroke-[2.5]"
             aria-label="关闭大图"
             title="关闭大图"
           >