perf: lazy-load stacktrace-js, focus-mode effects, and store-devtools

- Lazy-load stacktrace-js (~75KB source) via dynamic import() in the
  async _getStacktrace function — only loaded when an error occurs
- Defer FocusModeEffects (42KB source) registration to idle time via
  createEnvironmentInjector; reducer/selectors stay eager for
  app.component.ts, effects load via requestIdleCallback
- Move StoreDevtoolsModule to dynamic import in dev mode only,
  removing the static import from the bootstrap providers
- Add stacktrace-js transitive CJS deps to angular.json allowlist
- Add .catch() error handling on all lazy registration promises

Reduces initial main bundle by ~53KB raw / ~16KB gzipped (-9.9%).
Lighthouse FCP improves by ~80ms (1051ms → 970ms, -7.7%).

angular.json

@@ -47,6 +47,9 @@
               "typia",
               "electron-log",
               "stacktrace-js",
+              "stack-generator",
+              "stacktrace-gps",
+              "error-stack-parser",
               "spark-md5",
               "chrono-node",
               "dayjs",