fix(editor): loading style (#12537)

Closes: [BS-3555](https://linear.app/affine-design/issue/BS-3555/ui-attachment-loading-变量更新)
Closes: [BS-3559](https://linear.app/affine-design/issue/BS-3559/ui-图片-loading-变量更新)

### Dark
<img width="625" alt="Screenshot 2025-05-26 at 20 32 36" src="https://github.com/user-attachments/assets/93501e3d-8fc6-45f9-84a0-ac147e5c5f9f" />

### Light
<img width="623" alt="Screenshot 2025-05-26 at 20 32 25" src="https://github.com/user-attachments/assets/7d5bc128-6667-45b5-982d-dab3a22706a7" />

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **New Features**
  - Loading icons are now invoked as functions, allowing for more flexible and customizable rendering with parameters like size and progress.

- **Refactor**
  - Replaced theme-dependent and static loading icon references with a unified `LoadingIcon()` component across multiple components and blocks.
  - Removed legacy icon variants and simplified icon import statements, centralizing icon rendering logic.

- **Style**
  - Updated styles for loading and reload buttons to use theme-aware CSS variables.
  - Enlarged and repositioned loading indicators in image blocks for better visibility.

- **Bug Fixes**
  - Achieved consistent loading icon rendering across various blocks and components by standardizing icon invocation.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/affine/blocks/bookmark/src/components/bookmark-card.ts

@@ -1,5 +1,5 @@
 import { getEmbedCardIcons } from '@blocksuite/affine-block-embed';
-import { WebIcon16 } from '@blocksuite/affine-components/icons';
+import { LoadingIcon, WebIcon16 } from '@blocksuite/affine-components/icons';
 import { ImageProxyService } from '@blocksuite/affine-shared/adapters';
 import { ThemeProvider } from '@blocksuite/affine-shared/services';
 import { getHostName } from '@blocksuite/affine-shared/utils';
@@ -60,11 +60,11 @@ export class BookmarkCard extends SignalWatcher(
         : title;
 
     const theme = this.bookmark.std.get(ThemeProvider).theme;
-    const { LoadingIcon, EmbedCardBannerIcon } = getEmbedCardIcons(theme);
+    const { EmbedCardBannerIcon } = getEmbedCardIcons(theme);
     const imageProxyService = this.bookmark.store.get(ImageProxyService);
 
     const titleIcon = this.loading
-      ? LoadingIcon
+      ? LoadingIcon()
       : icon
         ? html`<img src=${imageProxyService.buildUrl(icon)} alt="icon" />`
         : WebIcon16;