fix: repoint dead angular.dev links in the Angular roadmap (#10259)

Five `@official@` links in the Angular roadmap point at angular.dev paths
that no longer exist. They are easy to miss because angular.dev is an SPA
that serves its app shell (HTTP 200) for every path, so a link checker
sees them as healthy while a reader gets the 404 page.

- Transitions & Triggers: the guide moved to /guide/legacy-animations/,
  the old URL matched the content file name rather than the route.
- Feature Modules / Creating Modules: /guide/ngmodules/feature-modules
  was removed, point both at the NgModules overview instead. The
  #how-to-make-a-feature-module anchor has no equivalent, so it is dropped.
- Pipes Precedence and Custom Pipes: pipe guides live under
  /guide/templates/pipes now, deep linked to the relevant sections.

Targets verified against the route table and content in angular/angular@main.

roadmaps/angular/content/creating-modules@9YhTXybJw2gszlqFeBtW3.md

@@ -4,4 +4,4 @@ Creating modules in Angular helps organize your application into manageable, coh
 
 Visit the following resources to learn more:
 
-- [@official@Feature Modules](https://angular.dev/guide/ngmodules/feature-modules)
+- [@official@NgModules](https://angular.dev/guide/ngmodules/overview)

roadmaps/angular/content/custom-pipes@BOYXGfULJRiP-XOo_lNX3.md

@@ -4,5 +4,5 @@ Pipes to transform strings, currency amounts, dates, and other data for display.
 
 Visit the following resources to learn more:
 
-- [@official@Custom Pipes for New Transforms](https://angular.dev/guide/pipes/transform-data)
+- [@official@Creating custom pipes](https://angular.dev/guide/templates/pipes#creating-custom-pipes)
 - [@video@Create a custom pipe video for Beginners](https://www.youtube.com/watch?v=P2587FN4Y0w)

roadmaps/angular/content/feature-modules@w_BazXvINFyxDCHmlznfy.md

@@ -4,6 +4,6 @@ Feature modules are `NgModules` for the purpose of organizing code. With feature
 
 Visit the following resources to learn more:
 
-- [@official@Feature Modules](https://angular.dev/guide/ngmodules/feature-modules#how-to-make-a-feature-module)
+- [@official@NgModules](https://angular.dev/guide/ngmodules/overview)
 - [@article@Feature module with lazy loading in Angular 15](https://medium.com/@jaydeepvpatil225/feature-module-with-lazy-loading-in-angular-15-53bb8e15d193)
 - [@video@Creating a Feature Module | Understanding Angular Modules](https://www.youtube.com/watch?v=VaPhaexVa1U)

roadmaps/angular/content/pipes-precedence@nZxZnzbQg9dz-SI65UHq9.md

@@ -8,5 +8,5 @@ You should always use parentheses to be sure Angular evaluates the expression as
 
 Visit the following resources to learn more:
 
-- [@official@Precedence](https://angular.dev/guide/pipes/precedence)
+- [@official@Pipe operator precedence](https://angular.dev/guide/templates/pipes#pipe-operator-precedence)
 - [@article@What is the precedence between pipe and ternary operators?](https://iq.js.org/questions/angular/what-is-the-precedence-between-pipe-and-ternary-operators)

roadmaps/angular/content/transitions--triggers@Iv2d4sgODqMPzA9gH6RAw.md

@@ -4,6 +4,6 @@ In Angular, transition states can be defined explicitly through the `state()` fu
 
 Visit the following resources to learn more:
 
-- [@official@Transition and Triggers](https://angular.dev/guide/animations/transition-and-triggers)
+- [@official@Transition and Triggers](https://angular.dev/guide/legacy-animations/transition-and-triggers)
 - [@video@Angular Animations: Learn the basics](https://www.youtube.com/watch?v=CGBcIz1tYec)
 - [@video@How to use trigger function in Angular Animations](https://www.youtube.com/watch?v=3_B4OV5M_Ag)