Bump @angular/compiler from 19.2.15 to 21.0.6

Bumps [@angular/compiler](https://github.com/angular/angular/tree/HEAD/packages/compiler) from 19.2.15 to 21.0.6.
- [Release notes](https://github.com/angular/angular/releases)
- [Changelog](https://github.com/angular/angular/blob/main/CHANGELOG.md)
- [Commits](https://github.com/angular/angular/commits/v21.0.6/packages/compiler)

---
updated-dependencies:
- dependency-name: "@angular/compiler"
  dependency-version: 21.0.6
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]