feat(editor): note extension (#11856)

Closes: BS-3200
Closes: BS-3201

blocksuite/affine/blocks/paragraph/src/store.ts

@@ -0,0 +1,17 @@
+import {
+  type StoreExtensionContext,
+  StoreExtensionProvider,
+} from '@blocksuite/affine-ext-loader';
+import { ParagraphBlockSchemaExtension } from '@blocksuite/affine-model';
+
+import { ParagraphBlockAdapterExtensions } from './adapters/extension';
+
+export class ParagraphStoreExtension extends StoreExtensionProvider {
+  override name = 'affine-paragraph-block';
+
+  override setup(context: StoreExtensionContext) {
+    super.setup(context);
+    context.register(ParagraphBlockSchemaExtension);
+    context.register(ParagraphBlockAdapterExtensions);
+  }
+}

blocksuite/affine/blocks/paragraph/src/view.ts

@@ -0,0 +1,67 @@
+import {
+  type ViewExtensionContext,
+  ViewExtensionProvider,
+} from '@blocksuite/affine-ext-loader';
+import { BlockViewExtension, FlavourExtension } from '@blocksuite/std';
+import { literal } from 'lit/static-html.js';
+
+import { ParagraphBlockConfigExtension } from './paragraph-block-config.js';
+import {
+  ParagraphKeymapExtension,
+  ParagraphTextKeymapExtension,
+} from './paragraph-keymap.js';
+
+const placeholders = {
+  text: "Type '/' for commands",
+  h1: 'Heading 1',
+  h2: 'Heading 2',
+  h3: 'Heading 3',
+  h4: 'Heading 4',
+  h5: 'Heading 5',
+  h6: 'Heading 6',
+  quote: '',
+};
+
+import { ParagraphBlockModel } from '@blocksuite/affine-model';
+import { z } from 'zod';
+
+import { effects } from './effects';
+
+const optionsSchema = z.object({
+  getPlaceholder: z
+    .function()
+    .args(z.instanceof(ParagraphBlockModel))
+    .returns(z.string()),
+});
+
+export class ParagraphViewExtension extends ViewExtensionProvider<
+  z.infer<typeof optionsSchema>
+> {
+  override name = 'affine-paragraph-block';
+
+  override schema = optionsSchema;
+
+  override effect(): void {
+    super.effect();
+    effects();
+  }
+
+  override setup(
+    context: ViewExtensionContext,
+    options?: z.infer<typeof optionsSchema>
+  ) {
+    super.setup(context);
+    const getPlaceholder =
+      options?.getPlaceholder ?? (model => placeholders[model.props.type]);
+
+    context.register([
+      FlavourExtension('affine:paragraph'),
+      BlockViewExtension('affine:paragraph', literal`affine-paragraph`),
+      ParagraphTextKeymapExtension,
+      ParagraphKeymapExtension,
+      ParagraphBlockConfigExtension({
+        getPlaceholder,
+      }),
+    ]);
+  }
+}