feat(core): editor setting service (#7956)

define editor setting schema in `packages/frontend/core/src/modules/editor-settting/schema.ts`

e.g.

```ts
const BSEditorSettingSchema = z.object({
  connector: z.object({
    stroke: z
      .union([
        z.string(),
        z.object({
          dark: z.string(),
          light: z.string(),
        }),
      ])
      .default('#000000'), // default is necessary
  }),
});
```

schema can be defined in a nested way. EditorSetting api is in flat way:

editorSetting api:

```ts
editorSetting.settings$ === {
  'connector.stroke': '#000000'
}
editorSetting.set('connector.stroke', '#000')
```

and use `expandFlattenObject` function can restore the flattened structure to a nested structure. nested structure is required by blocksuite

```ts
editorSetting.settings$.map(expandFlattenObject) === {
  connector: {
    stroke: '#000000'
  }
}
```

packages/frontend/core/src/modules/index.ts

@@ -6,6 +6,7 @@ import { configureCollectionModule } from './collection';
 import { configureDocLinksModule } from './doc-link';
 import { configureDocsSearchModule } from './docs-search';
 import { configureEditorModule } from './editor';
+import { configureEditorSettingModule } from './editor-settting';
 import { configureExplorerModule } from './explorer';
 import { configureFavoriteModule } from './favorite';
 import { configureFindInPageModule } from './find-in-page';
@@ -43,4 +44,5 @@ export function configureCommonModules(framework: Framework) {
   configureThemeEditorModule(framework);
   configureEditorModule(framework);
   configureSystemFontFamilyModule(framework);
+  configureEditorSettingModule(framework);
 }