fix(cli): only load sourcemap when --debug flag is enabled (#23752)

Loading the sourcemap file is prohibitively slow.
We don't need to do this unless we actually want to debug things.

```console
# with inline sourcemap
$ time cdk --help
cdk --help  6.32s user 1.66s system 106% cpu 7.510 total

# with linked sourcemap
$ time cdk --help
./bin/cdk --help  4.01s user 0.38s system 113% cpu 3.872 total

# without sourcemap
$ time cdk --help
./bin/cdk --help  0.65s user 0.12s system 91% cpu 0.839 total
```

Sourcemap support can be tested by running an unknown command:
```console
$ cdk unknown -v
[12:05:46] Error: Unknown command: unknown
    at main (/abc/node_modules/aws-cdk/lib/cli.ts:628:15)
    at exec4 (/abc/node_modules/aws-cdk/lib/cli.ts:384:18)
```

----

### All Submissions:

* [x] Have you followed the guidelines in our [Contributing guide?](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md)

### Adding new Construct Runtime Dependencies:

* [ ] This PR adds new construct runtime dependencies following the process described [here](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md/#adding-construct-runtime-dependencies)

### New Features

* [ ] Have you added the new feature to an [integration test](https://github.com/aws/aws-cdk/blob/main/INTEGRATION_TESTS.md)?
	* [ ] Did you use `yarn integ` to deploy the infrastructure and generate the snapshot (i.e. `yarn integ` without `--dry-run`)?

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: mrgrain

packages/aws-cdk/lib/api/index.ts

@@ -1,5 +1,3 @@
-import 'source-map-support/register';
-
 export * from './aws-auth/credentials';
 export * from './bootstrap';
 export * from './deploy-stack';

packages/aws-cdk/lib/cli.ts

@@ -1,7 +1,7 @@
-import 'source-map-support/register';
 import * as cxapi from '@aws-cdk/cx-api';
 import '@jsii/check-node/run';
 import * as chalk from 'chalk';
+import { install as enableSourceMapSupport } from 'source-map-support';
 
 import type { Argv } from 'yargs';
 import { SdkProvider } from '../lib/api/aws-auth';
@@ -285,6 +285,11 @@ if (!process.stdout.isTTY) {
 
 export async function exec(args: string[], synthesizer?: Synthesizer): Promise<number | void> {
   const argv = await parseCommandLineArguments(args);
+
+  if (argv.debug) {
+    enableSourceMapSupport();
+  }
+
   if (argv.verbose) {
     setLogLevel(argv.verbose);
 

packages/aws-cdk/package.json

@@ -49,7 +49,8 @@
       "test": "bin/cdk --version",
       "entryPoints": [
         "lib/index.js"
-      ]
+      ],
+      "sourcemap": "linked"
     }
   },
   "author": {
@@ -71,6 +72,7 @@
     "@types/promptly": "^3.0.2",
     "@types/semver": "^7.3.13",
     "@types/sinon": "^9.0.11",
+    "@types/source-map-support": "^0.5.6",
     "@types/table": "^6.0.0",
     "@types/uuid": "^8.3.4",
     "@types/wrap-ansi": "^3.0.0",

tools/@aws-cdk/node-bundle/src/api/bundle.ts

@@ -73,6 +73,13 @@ export interface BundleProps {
    * @default - no check.
    */
   readonly test?: string;
+
+  /**
+   * Basic sanity check to run against the created bundle.
+   *
+   * @default "inline"
+   */
+  readonly sourcemap?: 'linked' | 'inline' | 'external' | 'both';  
 }
 
 /**
@@ -148,6 +155,7 @@ export class Bundle {
   private readonly allowedLicenses: string[];
   private readonly dontAttribute?: string;
   private readonly test?: string;
+  private readonly sourcemap?: 'linked' | 'inline' | 'external' | 'both';
 
   private _bundle?: esbuild.BuildResult;
   private _dependencies?: Package[];
@@ -165,6 +173,7 @@ export class Bundle {
     this.allowedLicenses = props.allowedLicenses ?? DEFAULT_ALLOWED_LICENSES;
     this.dontAttribute = props.dontAttribute;
     this.entryPoints = {};
+    this.sourcemap = props.sourcemap;
 
     const entryPoints = props.entryPoints ?? (this.manifest.main ? [this.manifest.main] : []);
 
@@ -394,7 +403,7 @@ export class Bundle {
       bundle: true,
       target: 'node14',
       platform: 'node',
-      sourcemap: 'inline',
+      sourcemap: this.sourcemap ?? 'inline',
       metafile: true,
       treeShaking: true,
       absWorkingDir: this.packageDir,

yarn.lock

@@ -2260,6 +2260,13 @@
   resolved "https://registry.npmjs.org/@types/sinonjs__fake-timers/-/sinonjs__fake-timers-8.1.2.tgz#bf2e02a3dbd4aecaf95942ecd99b7402e03fad5e"
   integrity sha512-9GcLXF0/v3t80caGs5p2rRfkB+a8VBGLJZVih6CNFkx8IZ994wiKKLSRs9nuFwk1HevWs/1mnUmkApGrSGsShA==
 
+"@types/source-map-support@^0.5.6":
+  version "0.5.6"
+  resolved "https://registry.npmjs.org/@types/source-map-support/-/source-map-support-0.5.6.tgz#aa4a8c98ec73a1f1f30a813573a9b2154a6eb39a"
+  integrity sha512-b2nJ9YyXmkhGaa2b8VLM0kJ04xxwNyijcq12/kDoomCt43qbHBeK2SLNJ9iJmETaAj+bKUT05PQUu3Q66GvLhQ==
+  dependencies:
+    source-map "^0.6.0"
+
 "@types/stack-utils@^2.0.0":
   version "2.0.1"
   resolved "https://registry.npmjs.org/@types/stack-utils/-/stack-utils-2.0.1.tgz#20f18294f797f2209b5f65c8e3b5c8e8261d127c"