[armando-navarro]

Checklist

• Issue number for this PR: Move the repo's build and test targets off the deprecated @angular-devkit/build-angular builders #3806
• Docs included?: no. Repository tooling only, nothing in the published package or its docs changes.
• Test units included?: no new specs. The change is build configuration.
• Breaking change?: no.
• In a clean directory, yarn install, yarn test run successfully? yes, with npm: npm ci, then the build, lint and spec runs under Verification.

Description

Angular CLI 22 deprecated the builders in @angular-devkit/build-angular as part of ending its webpack support, and npm run build printed that warning on every run. The build and test targets now use the @angular/build builders of the same names, which take the same options. The reasoning is in #3806.

Changes

• angular.json: @angular/build:ng-packagr for build, @angular/build:karma for test. Options unchanged.
• karma.conf.js: the @angular-devkit/build-angular framework and plugin entries are gone. client.args, which src/test-config.ts reads for the emulator ports, is passed through as before.
• package.json: @angular/build replaces @angular-devkit/build-angular in the devDependencies.
• package-lock.json: regenerated. 364 entries gone (webpack, @ngtools/webpack, babel-loader, copy-webpack-plugin and their dependencies), none added, no version changes. Regenerated with npm 10.9.9, the npm bundled with the Node 22 that CI runs: npm 11 prunes three nested @types/node entries that npm 10 requires.

Behavior to know

• The spec bundle is built by esbuild instead of webpack.
• The served spec bundle is written to dist/test-out/. Running npm run build (which starts with rimraf dist) while npm run test:watch is open removes it until the next rebuild.
• The coverageIstanbulReporter block and its reporter plugin in karma.conf.js stay as they are.
• Coverage did not run on the old builder either (karma-coverage is not installed), so nothing that worked stops working.
• Turning coverage on takes istanbul-lib-instrument, an optional peer of @angular/build that goes with the webpack tree, plus either karma-coverage or a coverage-istanbul entry in reporters for the istanbul reporter that is already installed.

Verification

• Build, lint, test:node (385 specs) pass. The build prints no deprecation warning.
• Chrome 155 and Firefox 158, each through firebase-tools emulators:exec: 112 of 160 executed, 48 skipped by pending(). The spec lists matched by name on both builders.
• The packed angular-fire-22.0.0.tgz built from the same commit with the old builder and with this one has the same SHA-1, 13a703e2d9bd0fb9ffb842ae68238b0e18cd302f, so the published package is unchanged.

Fixes #3806