build: remove redundant ng-dev unbundled js and update package default export to mjs bundle.

This fixes an issue where the unbundled version was being used.

Fixes https://github.com/angular/angular-cli/actions/runs/20734048902/job/59527805888?pr=32189

Author: alan-agius4

ng-dev/BUILD.bazel

@@ -129,7 +129,6 @@ npm_package(
     srcs = [
         "package.json",
         ":bundles",
-        ":ng-dev",
         ":types",
     ],
     package = "@angular/ng-dev",

ng-dev/package.json

@@ -7,7 +7,7 @@
   "exports": {
     ".": {
       "types": "./index.d.ts",
-      "default": "./index.js"
+      "default": "./bundles/index.mjs"
     },
     "./*": {
       "types": "./*.d.ts",