feat(docs): migrate bs docs

blocksuite/docs-site/components/blocks/attachment-block.md

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+# Attachment Block
+
+This is a block used to place attachment content. It supports optional style configurations to display as cards of different styles.
+
+## Reference
+
+- [`AttachmentBlockSchema`](/api/@blocksuite/blocks/variables/AttachmentBlockSchema.html)
+- [`AttachmentBlockService`](/api/@blocksuite/blocks/classes/AttachmentBlockService.html)