refactor: upgrade to Angular 19

[arturovt]

Note: This commit contains breaking changes, as we now support Angular 19 as the minimum version.

NgFor has been replaced with Angular’s native control flow (@for (...)). Values have been updated to be signal-based, since signals serve as the communication protocol between components and views in Angular. They automatically trigger change detection when their values change.

[dhilt]

@arturovt I will definitely look into this and address it as soon as I have an available time window. Thank you very much for the PR!

[dhilt]

@arturovt Well, this looks very good so far, except for testing. I tried to find some quick fix, but failed. After all my local attempts I got stuck with the same error as on CI:

  An error was thrown in afterAll
  Error: Errors during JIT compilation of template for UiScrollComponent: Unexpected character "EOF" (Do you have an unescaped "{" in your template? Use "{{ '{' }}") to escape it.) ("
  </div>
  }
  <div data-padding-forward></div>[ERROR ->]"): ng:///UiScrollComponent/template.html@18:32, Invalid ICU message. Missing '}'. ("
  </div>
  }
  <div data-padding-forward></div>[ERROR ->]"): ng:///UiScrollComponent/template.html@18:32

What do you think, can we make it work?

[dhilt]

Welcoming the arrival of v4: https://github.com/dhilt/ngx-ui-scroll/releases/tag/v4.0.0