feat: add .ts extensions to all relative imports for rewriteRelativeImportExtensions

Migrates all relative import/export specifiers across the repo to include
explicit .ts/.tsx file extensions. This enables TypeScript's
rewriteRelativeImportExtensions compiler option to produce correct .js
extensions in compiled output, fixing ESM resolution under Node.js.

Also includes:
- heft-typescript-plugin: inject rewriteRelativeImportExtensions and
  allowImportingTsExtensions in tsconfigLoader; enhance wrapWriteFile
  to rewrite .js specifiers when jsExtensionOverride is set; remove
  the old addJsExtensionToImports approach
- ESLint import/extensions rule added to local-eslint-config
- ESLint rule disabled for ts-loader and composite-test projects
- require() calls use .js extensions (not rewritten by TS)
- esm-node-import-test: new build-test validating ESM imports work
- rush.json: register esm-node-import-test project

Fixes #5644

Author: iclanton

apps/api-documenter/src/cli/ApiDocumenterCommandLine.ts

@@ -3,9 +3,9 @@
 
 import { CommandLineParser } from '@rushstack/ts-command-line';
 
-import { MarkdownAction } from './MarkdownAction';
-import { YamlAction } from './YamlAction';
-import { GenerateAction } from './GenerateAction';
+import { MarkdownAction } from './MarkdownAction.ts';
+import { YamlAction } from './YamlAction.ts';
+import { GenerateAction } from './GenerateAction.ts';
 
 export class ApiDocumenterCommandLine extends CommandLineParser {
   public constructor() {

apps/api-documenter/src/cli/GenerateAction.ts

@@ -5,11 +5,11 @@ import * as path from 'node:path';
 
 import { FileSystem } from '@rushstack/node-core-library';
 
-import type { ApiDocumenterCommandLine } from './ApiDocumenterCommandLine';
-import { BaseAction } from './BaseAction';
-import { DocumenterConfig } from '../documenters/DocumenterConfig';
-import { ExperimentalYamlDocumenter } from '../documenters/ExperimentalYamlDocumenter';
-import { MarkdownDocumenter } from '../documenters/MarkdownDocumenter';
+import type { ApiDocumenterCommandLine } from './ApiDocumenterCommandLine.ts';
+import { BaseAction } from './BaseAction.ts';
+import { DocumenterConfig } from '../documenters/DocumenterConfig.ts';
+import { ExperimentalYamlDocumenter } from '../documenters/ExperimentalYamlDocumenter.ts';
+import { MarkdownDocumenter } from '../documenters/MarkdownDocumenter.ts';
 
 export class GenerateAction extends BaseAction {
   public constructor(parser: ApiDocumenterCommandLine) {

apps/api-documenter/src/cli/MarkdownAction.ts

@@ -1,9 +1,9 @@
 // Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
 // See LICENSE in the project root for license information.
 
-import type { ApiDocumenterCommandLine } from './ApiDocumenterCommandLine';
-import { BaseAction } from './BaseAction';
-import { MarkdownDocumenter } from '../documenters/MarkdownDocumenter';
+import type { ApiDocumenterCommandLine } from './ApiDocumenterCommandLine.ts';
+import { BaseAction } from './BaseAction.ts';
+import { MarkdownDocumenter } from '../documenters/MarkdownDocumenter.ts';
 
 export class MarkdownAction extends BaseAction {
   public constructor(parser: ApiDocumenterCommandLine) {

apps/api-documenter/src/cli/YamlAction.ts

@@ -6,10 +6,10 @@ import type {
   IRequiredCommandLineChoiceParameter
 } from '@rushstack/ts-command-line';
 
-import type { ApiDocumenterCommandLine } from './ApiDocumenterCommandLine';
-import { BaseAction } from './BaseAction';
-import { YamlDocumenter, type YamlFormat } from '../documenters/YamlDocumenter';
-import { OfficeYamlDocumenter } from '../documenters/OfficeYamlDocumenter';
+import type { ApiDocumenterCommandLine } from './ApiDocumenterCommandLine.ts';
+import { BaseAction } from './BaseAction.ts';
+import { YamlDocumenter, type YamlFormat } from '../documenters/YamlDocumenter.ts';
+import { OfficeYamlDocumenter } from '../documenters/OfficeYamlDocumenter.ts';
 
 export class YamlAction extends BaseAction {
   private readonly _officeParameter: CommandLineFlagParameter;

apps/api-documenter/src/documenters/DocumenterConfig.ts

@@ -5,7 +5,7 @@ import * as path from 'node:path';
 
 import { JsonSchema, JsonFile, NewlineKind } from '@rushstack/node-core-library';
 
-import type { IConfigFile } from './IConfigFile';
+import type { IConfigFile } from './IConfigFile.ts';
 import apiDocumenterSchema from '../schemas/api-documenter.schema.json';
 
 /**

apps/api-documenter/src/documenters/ExperimentalYamlDocumenter.ts

@@ -4,10 +4,10 @@
 import { type DocComment, DocInlineTag } from '@microsoft/tsdoc';
 import { type ApiModel, type ApiItem, ApiItemKind, ApiDocumentedItem } from '@microsoft/api-extractor-model';
 
-import type { IConfigTableOfContents } from './IConfigFile';
-import type { IYamlTocItem, IYamlTocFile } from '../yaml/IYamlTocFile';
-import { YamlDocumenter } from './YamlDocumenter';
-import type { DocumenterConfig } from './DocumenterConfig';
+import type { IConfigTableOfContents } from './IConfigFile.ts';
+import type { IYamlTocItem, IYamlTocFile } from '../yaml/IYamlTocFile.ts';
+import { YamlDocumenter } from './YamlDocumenter.ts';
+import type { DocumenterConfig } from './DocumenterConfig.ts';
 
 /**
  * EXPERIMENTAL - This documenter is a prototype of a new config file driven mode of operation for

apps/api-documenter/src/documenters/IConfigFile.ts

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
 // See LICENSE in the project root for license information.
 
-import type { IYamlTocFile } from '../yaml/IYamlTocFile';
+import type { IYamlTocFile } from '../yaml/IYamlTocFile.ts';
 
 /**
  * Typescript interface describing the config schema for toc.yml file format.

apps/api-documenter/src/documenters/MarkdownDocumenter.ts

@@ -49,22 +49,22 @@ import {
   type IFindApiItemsResult
 } from '@microsoft/api-extractor-model';
 
-import { CustomDocNodes } from '../nodes/CustomDocNodeKind';
-import { DocHeading } from '../nodes/DocHeading';
-import { DocTable } from '../nodes/DocTable';
-import { DocEmphasisSpan } from '../nodes/DocEmphasisSpan';
-import { DocTableRow } from '../nodes/DocTableRow';
-import { DocTableCell } from '../nodes/DocTableCell';
-import { DocNoteBox } from '../nodes/DocNoteBox';
-import { Utilities } from '../utils/Utilities';
-import { CustomMarkdownEmitter } from '../markdown/CustomMarkdownEmitter';
-import { PluginLoader } from '../plugin/PluginLoader';
+import { CustomDocNodes } from '../nodes/CustomDocNodeKind.ts';
+import { DocHeading } from '../nodes/DocHeading.ts';
+import { DocTable } from '../nodes/DocTable.ts';
+import { DocEmphasisSpan } from '../nodes/DocEmphasisSpan.ts';
+import { DocTableRow } from '../nodes/DocTableRow.ts';
+import { DocTableCell } from '../nodes/DocTableCell.ts';
+import { DocNoteBox } from '../nodes/DocNoteBox.ts';
+import { Utilities } from '../utils/Utilities.ts';
+import { CustomMarkdownEmitter } from '../markdown/CustomMarkdownEmitter.ts';
+import { PluginLoader } from '../plugin/PluginLoader.ts';
 import {
   type IMarkdownDocumenterFeatureOnBeforeWritePageArgs,
   MarkdownDocumenterFeatureContext
-} from '../plugin/MarkdownDocumenterFeature';
-import type { DocumenterConfig } from './DocumenterConfig';
-import { MarkdownDocumenterAccessor } from '../plugin/MarkdownDocumenterAccessor';
+} from '../plugin/MarkdownDocumenterFeature.ts';
+import type { DocumenterConfig } from './DocumenterConfig.ts';
+import { MarkdownDocumenterAccessor } from '../plugin/MarkdownDocumenterAccessor.ts';
 
 export interface IMarkdownDocumenterOptions {
   apiModel: ApiModel;

apps/api-documenter/src/documenters/OfficeYamlDocumenter.ts

@@ -9,9 +9,9 @@ import type { ApiModel } from '@microsoft/api-extractor-model';
 import { FileSystem } from '@rushstack/node-core-library';
 import { Colorize } from '@rushstack/terminal';
 
-import type { IYamlTocItem } from '../yaml/IYamlTocFile';
-import type { IYamlItem } from '../yaml/IYamlApiFile';
-import { YamlDocumenter } from './YamlDocumenter';
+import type { IYamlTocItem } from '../yaml/IYamlTocFile.ts';
+import type { IYamlItem } from '../yaml/IYamlApiFile.ts';
+import { YamlDocumenter } from './YamlDocumenter.ts';
 
 interface ISnippetsFile {
   /**

apps/api-documenter/src/documenters/YamlDocumenter.ts

@@ -60,11 +60,11 @@ import type {
   IYamlReference,
   IYamlReferenceSpec,
   IYamlInheritanceTree
-} from '../yaml/IYamlApiFile';
-import type { IYamlTocFile, IYamlTocItem } from '../yaml/IYamlTocFile';
-import { Utilities } from '../utils/Utilities';
-import { CustomMarkdownEmitter } from '../markdown/CustomMarkdownEmitter';
-import { convertUDPYamlToSDP } from '../utils/ToSdpConvertHelper';
+} from '../yaml/IYamlApiFile.ts';
+import type { IYamlTocFile, IYamlTocItem } from '../yaml/IYamlTocFile.ts';
+import { Utilities } from '../utils/Utilities.ts';
+import { CustomMarkdownEmitter } from '../markdown/CustomMarkdownEmitter.ts';
+import { convertUDPYamlToSDP } from '../utils/ToSdpConvertHelper.ts';
 import typescriptSchema from '../yaml/typescript.schema.json';
 
 const yamlApiSchema: JsonSchema = JsonSchema.fromLoadedObject(typescriptSchema);