fix(ivy): handle &ngsp; in i18n translations correctly (#31479)

Prior to this commit, the `` unicode symbol that represents `&ngsp` in translations was not handled correctly, i.e. was not replaced with a whitespace, thus appearing on a screen. This commit adds post-processing and replaces the mentioned symbol with a whitespace.

PR Close #31479

packages/core/test/acceptance/i18n_spec.ts

@@ -48,6 +48,14 @@ onlyInIvy('Ivy i18n logic').describe('runtime i18n', () => {
     expect(fixture.nativeElement.innerHTML).toBe('<div>Bonjour Angular</div>');
   });
 
+  it('should support &ngsp; in translatable sections', () => {
+    // note: the `` unicode symbol represents the `&ngsp;` in translations
+    ɵi18nConfigureLocalize({translations: {'text ||': 'texte ||'}});
+    const fixture = initWithTemplate(AppCompWithWhitespaces, `<div i18n>text |&ngsp;|</div>`);
+
+    expect(fixture.nativeElement.innerHTML).toEqual(`<div>texte | |</div>`);
+  });
+
   it('should support interpolations with complex expressions', () => {
     ɵi18nConfigureLocalize({
       translations:
@@ -1503,6 +1511,14 @@ class AppComp {
   count = 0;
 }
 
+@Component({
+  selector: 'app-comp-with-whitespaces',
+  template: ``,
+  preserveWhitespaces: true,
+})
+class AppCompWithWhitespaces {
+}
+
 @Directive({
   selector: '[tplRef]',
 })