refactor(editor): unify directories naming (#11516)

**Directory Structure Changes**

- Renamed multiple block-related directories by removing the "block-" prefix:
  - `block-attachment` → `attachment`
  - `block-bookmark` → `bookmark`
  - `block-callout` → `callout`
  - `block-code` → `code`
  - `block-data-view` → `data-view`
  - `block-database` → `database`
  - `block-divider` → `divider`
  - `block-edgeless-text` → `edgeless-text`
  - `block-embed` → `embed`

blocksuite/affine/blocks/code/src/adapters/plain-text.ts

@@ -0,0 +1,26 @@
+import { CodeBlockSchema } from '@blocksuite/affine-model';
+import {
+  BlockPlainTextAdapterExtension,
+  type BlockPlainTextAdapterMatcher,
+} from '@blocksuite/affine-shared/adapters';
+import type { DeltaInsert } from '@blocksuite/store';
+
+export const codeBlockPlainTextAdapterMatcher: BlockPlainTextAdapterMatcher = {
+  flavour: CodeBlockSchema.model.flavour,
+  toMatch: () => false,
+  fromMatch: o => o.node.flavour === CodeBlockSchema.model.flavour,
+  toBlockSnapshot: {},
+  fromBlockSnapshot: {
+    enter: (o, context) => {
+      const text = (o.node.props.text ?? { delta: [] }) as {
+        delta: DeltaInsert[];
+      };
+      const buffer = text.delta.map(delta => delta.insert).join('');
+      context.textBuffer.content += buffer;
+      context.textBuffer.content += '\n';
+    },
+  },
+};
+
+export const CodeBlockPlainTextAdapterExtension =
+  BlockPlainTextAdapterExtension(codeBlockPlainTextAdapterMatcher);