build(deps): bump @angular/compiler in /frontend/src/angular

Bumps [@angular/compiler](https://github.com/angular/angular/tree/HEAD/packages/compiler) from 21.0.3 to 21.0.7.
- [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/v21.0.7/packages/compiler)

---
updated-dependencies:
- dependency-name: "@angular/compiler"
  dependency-version: 21.0.7
  dependency-type: direct:production
...

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