refactor(core): indexer & embedding -> embedding (#12387)

### TL;DR

refactor: rename settings, indexer embedding -> embedding

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

- **Refactor**
  - Unified naming in workspace settings from "Indexer & Embedding" to "Embedding" for improved clarity.
  - Updated sidebar labels, tab keys, and test IDs to reflect the new naming convention.
  - Streamlined the layout and organization of the embedding settings interface for a more consistent user experience.
  - Simplified the export and component structure for embedding settings.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/core/src/desktop/dialogs/setting/workspace-setting/index.tsx

@@ -2,7 +2,7 @@ import { useWorkspaceInfo } from '@affine/core/components/hooks/use-workspace-in
 import { ServerService } from '@affine/core/modules/cloud';
 import type { SettingTab } from '@affine/core/modules/dialogs/constant';
 import { WorkspaceService } from '@affine/core/modules/workspace';
-import { IndexerEmbeddingSettings } from '@affine/core/modules/workspace-indexer-embedding';
+import { EmbeddingSettings } from '@affine/core/modules/workspace-indexer-embedding';
 import { ServerDeploymentType } from '@affine/graphql';
 import { useI18n } from '@affine/i18n';
 import {
@@ -54,8 +54,8 @@ export const WorkspaceSetting = ({
       return <WorkspaceSettingLicense onCloseSetting={onCloseSetting} />;
     case 'workspace:integrations':
       return <IntegrationSetting />;
-    case 'workspace:indexer-embedding':
-      return <IndexerEmbeddingSettings />;
+    case 'workspace:embedding':
+      return <EmbeddingSettings />;
     default:
       return null;
   }
@@ -110,10 +110,13 @@ export const useWorkspaceSettingList = (): SettingSidebarItem[] => {
         testId: 'workspace-setting:storage',
       },
       {
-        key: 'workspace:indexer-embedding',
-        title: t['Indexer & Embedding'](),
+        key: 'workspace:embedding',
+        title:
+          t[
+            'com.affine.settings.workspace.indexer-embedding.embedding.title'
+          ](),
         icon: <SettingsIcon />,
-        testId: 'workspace-setting:indexer-embedding',
+        testId: 'workspace-setting:embedding',
       },
       showBilling && {
         key: 'workspace:billing' as SettingTab,