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/embed/src/common/utils.ts

@@ -9,13 +9,11 @@ import {
   EmbedCardLightHorizontalIcon,
   EmbedCardLightListIcon,
   EmbedCardLightVerticalIcon,
-  getLoadingIconWith,
 } from '@blocksuite/affine-components/icons';
 import { ColorScheme } from '@blocksuite/affine-model';
 import type { TemplateResult } from 'lit';
 
 type EmbedCardIcons = {
-  LoadingIcon: TemplateResult<1>;
   EmbedCardBannerIcon: TemplateResult<1>;
   EmbedCardHorizontalIcon: TemplateResult<1>;
   EmbedCardListIcon: TemplateResult<1>;
@@ -24,11 +22,8 @@ type EmbedCardIcons = {
 };
 
 export function getEmbedCardIcons(theme: ColorScheme): EmbedCardIcons {
-  const LoadingIcon = getLoadingIconWith(theme);
-
   if (theme === ColorScheme.Light) {
     return {
-      LoadingIcon,
       EmbedCardBannerIcon: EmbedCardLightBannerIcon,
       EmbedCardHorizontalIcon: EmbedCardLightHorizontalIcon,
       EmbedCardListIcon: EmbedCardLightListIcon,
@@ -37,7 +32,6 @@ export function getEmbedCardIcons(theme: ColorScheme): EmbedCardIcons {
     };
   } else {
     return {
-      LoadingIcon,
       EmbedCardBannerIcon: EmbedCardDarkBannerIcon,
       EmbedCardHorizontalIcon: EmbedCardDarkHorizontalIcon,
       EmbedCardListIcon: EmbedCardDarkListIcon,