remove unused CODY_APP esbuild config and entrypoint (#63438)

Cody App was removed in Dec 2023, and the `app/main.tsx` file has not
existed for a long time.

## Test plan

n/a

Author: sqs

client/web/dev/esbuild/config.ts

@@ -5,10 +5,10 @@ import type * as esbuild from 'esbuild'
 
 import { ROOT_PATH, STATIC_ASSETS_PATH } from '@sourcegraph/build-config'
 import {
-    stylePlugin,
-    packageResolutionPlugin,
-    monacoPlugin,
     buildTimerPlugin,
+    monacoPlugin,
+    packageResolutionPlugin,
+    stylePlugin,
     workerPlugin,
 } from '@sourcegraph/build-config/src/esbuild/plugins'
 import { MONACO_LANGUAGES_AND_FEATURES } from '@sourcegraph/build-config/src/monaco-editor'
@@ -23,12 +23,10 @@ import { WEB_BUILD_MANIFEST_FILENAME, webManifestBuilder } from './webmanifest'
  */
 export function esbuildBuildOptions(ENVIRONMENT_CONFIG: EnvironmentConfig): esbuild.BuildOptions {
     return {
-        entryPoints: ENVIRONMENT_CONFIG.CODY_APP
-            ? [path.join(ROOT_PATH, 'client/web/src/enterprise/app/main.tsx')]
-            : [
-                  path.join(ROOT_PATH, 'client/web/src/enterprise/main.tsx'),
-                  path.join(ROOT_PATH, 'client/web/src/enterprise/embed/embedMain.tsx'),
-              ],
+        entryPoints: [
+            path.join(ROOT_PATH, 'client/web/src/enterprise/main.tsx'),
+            path.join(ROOT_PATH, 'client/web/src/enterprise/embed/embedMain.tsx'),
+        ],
         bundle: true,
         minify: ENVIRONMENT_CONFIG.NODE_ENV === 'production',
         treeShaking: true,

client/web/dev/utils/environment-config.ts

@@ -62,7 +62,6 @@ export const ENVIRONMENT_CONFIG = {
      * ----------------------------------------
      */
     SOURCEGRAPHDOTCOM_MODE: getEnvironmentBoolean('SOURCEGRAPHDOTCOM_MODE'),
-    CODY_APP: getEnvironmentBoolean('CODY_APP'),
 
     // Is reporting to Sentry enabled.
     ENABLE_SENTRY: getEnvironmentBoolean('ENABLE_SENTRY'),