feat(editor): block comment extension (#12980)

#### PR Dependency Tree


* **PR #12980** 👈

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blocksuite/affine/blocks/embed-doc/src/embed-synced-doc-block/configs/toolbar.ts

@@ -16,6 +16,7 @@ import {
 import { REFERENCE_NODE } from '@blocksuite/affine-shared/consts';
 import {
   ActionPlacement,
+  blockCommentToolbarButton,
   EditorSettingProvider,
   type LinkEventType,
   type OpenDocMode,
@@ -225,6 +226,10 @@ const builtinToolbarConfig = {
     openDocActionGroup,
     conversionsActionGroup,
     captionAction,
+    {
+      id: 'e.comment',
+      ...blockCommentToolbarButton,
+    },
     {
       placement: ActionPlacement.More,
       id: 'a.clipboard',

blocksuite/affine/blocks/embed-doc/src/embed-synced-doc-block/embed-synced-doc-block.ts

@@ -232,6 +232,7 @@ export class EmbedSyncedDocBlockComponent extends EmbedBlockComponent<EmbedSynce
             surface: false,
             selected: this.selected$.value,
             'show-hover-border': true,
+            'comment-highlighted': this.isCommentHighlighted,
           })}
           @click=${this._handleClick}
           style=${containerStyleMap}

blocksuite/affine/blocks/embed-doc/src/embed-synced-doc-block/styles.ts

@@ -57,6 +57,9 @@ export const blockStyles = css`
     border-radius: 8px;
     overflow: hidden;
   }
+  .affine-embed-synced-doc-container.comment-highlighted {
+    outline: 2px solid ${unsafeCSSVarV2('block/comment/highlightUnderline')};
+  }
   .affine-embed-synced-doc-container.show-hover-border:hover {
     border-color: var(--affine-border-color);
   }