fix(sdk): use explicit index.js specifier for entities barrel import

Bare `../../entities` is a directory specifier, which Node's ESM
resolver rejects (ERR_UNSUPPORTED_DIR_IMPORT) since the package is
"type": "module". Points at the explicit barrel file instead.

Author: Reversean

packages/sdk/src/tools/facades/BaseToolFacade.spec.ts

@@ -1,8 +1,8 @@
 /* eslint-disable jsdoc/require-jsdoc,@typescript-eslint/no-magic-numbers */
 
 import { describe, expect, it } from '@jest/globals';
-import type { BlockToolConstructor, BlockToolData } from '../../entities';
-import { BlockToolOptionKey, ToolType } from '../../entities';
+import type { BlockToolConstructor, BlockToolData } from '../../entities/index.js';
+import { BlockToolOptionKey, ToolType } from '../../entities/index.js';
 import type { ToolOptions } from './BaseToolFacade.js';
 import { UserToolOptions } from './BaseToolFacade.js';
 import { BlockToolFacade } from './BlockToolFacade.js';

packages/sdk/src/tools/facades/BaseToolFacade.ts

@@ -4,12 +4,12 @@ import type {
 import { isFunction } from '@editorjs/helpers';
 import { type BlockToolFacade } from './BlockToolFacade.js';
 import { type InlineToolFacade } from './InlineToolFacade.js';
-import { ToolType, BaseToolOptionKey } from '../../entities';
+import { ToolType, BaseToolOptionKey } from '../../entities/index.js';
 import { type BlockTuneFacade } from './BlockTuneFacade.js';
 import type {
   BlockTool, BlockToolConstructor, InlineTool, InlineToolConstructor, BlockTuneConstructor,
   ToolTypeToOptions, ToolStaticOptions, BlockToolOptions, InlineToolOptions, BlockTuneOptions
-} from '../../entities';
+} from '../../entities/index.js';
 import type { EditorAPI } from '../../api';
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any -- need to allow any type here so extended interfaces pass